diff --git a/flow/embedded_views.h b/flow/embedded_views.h
index c16426980f88d..6985c37e5b8c0 100644
--- a/flow/embedded_views.h
+++ b/flow/embedded_views.h
@@ -6,7 +6,6 @@
 #define FLUTTER_FLOW_EMBEDDED_VIEWS_H_
 
 #include <memory>
-#include <utility>
 #include <vector>
 
 #include "flutter/display_list/dl_builder.h"
@@ -52,7 +51,7 @@ class ImageFilterMutation {
  public:
   ImageFilterMutation(std::shared_ptr<const DlImageFilter> filter,
                       const SkRect& filter_rect)
-      : filter_(std::move(filter)), filter_rect_(filter_rect) {}
+      : filter_(filter), filter_rect_(filter_rect) {}
 
   const DlImageFilter& GetFilter() const { return *filter_; }
   const SkRect& GetFilterRect() const { return filter_rect_; }
@@ -111,7 +110,7 @@ class Mutator {
   explicit Mutator(const SkMatrix& matrix)
       : type_(kTransform), matrix_(matrix) {}
   explicit Mutator(const int& alpha) : type_(kOpacity), alpha_(alpha) {}
-  explicit Mutator(const std::shared_ptr<const DlImageFilter>& filter,
+  explicit Mutator(std::shared_ptr<const DlImageFilter> filter,
                    const SkRect& filter_rect)
       : type_(kBackdropFilter),
         filter_mutation_(
@@ -271,7 +270,7 @@ class EmbeddedViewParams {
                      MutatorsStack mutators_stack)
       : matrix_(matrix),
         size_points_(size_points),
-        mutators_stack_(std::move(mutators_stack)) {
+        mutators_stack_(mutators_stack) {
     SkPath path;
     SkRect starting_rect = SkRect::MakeSize(size_points);
     path.addRect(starting_rect);
@@ -296,7 +295,7 @@ class EmbeddedViewParams {
   // Pushes the stored DlImageFilter object to the mutators stack.
   //
   // `filter_rect` is in global coordinates.
-  void PushImageFilter(const std::shared_ptr<const DlImageFilter>& filter,
+  void PushImageFilter(std::shared_ptr<const DlImageFilter> filter,
                        const SkRect& filter_rect) {
     mutators_stack_.PushBackdropFilter(filter, filter_rect);
   }
@@ -345,7 +344,7 @@ class EmbedderViewSlice {
 
 class DisplayListEmbedderViewSlice : public EmbedderViewSlice {
  public:
-  explicit DisplayListEmbedderViewSlice(SkRect view_bounds);
+  DisplayListEmbedderViewSlice(SkRect view_bounds);
   ~DisplayListEmbedderViewSlice() override = default;
 
   DlCanvas* canvas() override;
@@ -392,7 +391,7 @@ class ExternalViewEmbedder {
       SkISize frame_size,
       GrDirectContext* context,
       double device_pixel_ratio,
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) = 0;
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) = 0;
 
   virtual void PrerollCompositeEmbeddedView(
       int64_t view_id,
@@ -403,7 +402,7 @@ class ExternalViewEmbedder {
   // after it does any requisite tasks needed to bring itself to a valid state.
   // Returns kSuccess if the view embedder is already in a valid state.
   virtual PostPrerollResult PostPrerollAction(
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
     return PostPrerollResult::kSuccess;
   }
 
@@ -433,7 +432,7 @@ class ExternalViewEmbedder {
   // returns false.
   virtual void EndFrame(
       bool should_resubmit_frame,
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {}
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {}
 
   // Whether the embedder should support dynamic thread merging.
   //
@@ -469,7 +468,7 @@ class ExternalViewEmbedder {
   // See also: |PushVisitedPlatformView| for pushing platform view ids to the
   // visited platform views list.
   virtual void PushFilterToVisitedPlatformViews(
-      const std::shared_ptr<const DlImageFilter>& filter,
+      std::shared_ptr<const DlImageFilter> filter,
       const SkRect& filter_rect) {}
 
  private:
diff --git a/flow/testing/mock_embedder.cc b/flow/testing/mock_embedder.cc
index 1f86912fdc549..ae41675b6f771 100644
--- a/flow/testing/mock_embedder.cc
+++ b/flow/testing/mock_embedder.cc
@@ -28,7 +28,7 @@ void MockViewEmbedder::BeginFrame(
     SkISize frame_size,
     GrDirectContext* context,
     double device_pixel_ratio,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {}
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {}
 
 // |ExternalViewEmbedder|
 void MockViewEmbedder::PrerollCompositeEmbeddedView(
diff --git a/flow/testing/mock_embedder.h b/flow/testing/mock_embedder.h
index 5ea8fdf8a7cbc..164d7baff79e3 100644
--- a/flow/testing/mock_embedder.h
+++ b/flow/testing/mock_embedder.h
@@ -25,11 +25,11 @@ class MockViewEmbedder : public ExternalViewEmbedder {
   void CancelFrame() override;
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override;
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   void PrerollCompositeEmbeddedView(
diff --git a/shell/common/rasterizer_unittests.cc b/shell/common/rasterizer_unittests.cc
index 10085e66ade0e..1e21d0d8f1ecb 100644
--- a/shell/common/rasterizer_unittests.cc
+++ b/shell/common/rasterizer_unittests.cc
@@ -89,23 +89,21 @@ class MockExternalViewEmbedder : public ExternalViewEmbedder {
  public:
   MOCK_METHOD(DlCanvas*, GetRootCanvas, (), (override));
   MOCK_METHOD(void, CancelFrame, (), (override));
-  MOCK_METHOD(
-      void,
-      BeginFrame,
-      (SkISize frame_size,
-       GrDirectContext* context,
-       double device_pixel_ratio,
-       const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger),
-      (override));
+  MOCK_METHOD(void,
+              BeginFrame,
+              (SkISize frame_size,
+               GrDirectContext* context,
+               double device_pixel_ratio,
+               fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger),
+              (override));
   MOCK_METHOD(void,
               PrerollCompositeEmbeddedView,
               (int64_t view_id, std::unique_ptr<EmbeddedViewParams> params),
               (override));
-  MOCK_METHOD(
-      PostPrerollResult,
-      PostPrerollAction,
-      (const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger),
-      (override));
+  MOCK_METHOD(PostPrerollResult,
+              PostPrerollAction,
+              (fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger),
+              (override));
   MOCK_METHOD(DlCanvas*, CompositeEmbeddedView, (int64_t view_id), (override));
   MOCK_METHOD(void,
               SubmitFrame,
@@ -113,12 +111,11 @@ class MockExternalViewEmbedder : public ExternalViewEmbedder {
                const std::shared_ptr<impeller::AiksContext>& aiks_context,
                std::unique_ptr<SurfaceFrame> frame),
               (override));
-  MOCK_METHOD(
-      void,
-      EndFrame,
-      (bool should_resubmit_frame,
-       const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger),
-      (override));
+  MOCK_METHOD(void,
+              EndFrame,
+              (bool should_resubmit_frame,
+               fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger),
+              (override));
   MOCK_METHOD(bool, SupportsDynamicThreadMerging, (), (override));
 };
 }  // namespace
@@ -202,8 +199,7 @@ TEST(RasterizerTest,
   framebuffer_info.supports_readback = true;
 
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, framebuffer_info,
+      /*surface=*/nullptr, framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(true));
@@ -275,8 +271,7 @@ TEST(
   SurfaceFrame::FramebufferInfo framebuffer_info;
   framebuffer_info.supports_readback = true;
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, framebuffer_info,
+      /*surface=*/nullptr, framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(true));
@@ -348,8 +343,7 @@ TEST(
   framebuffer_info.supports_readback = true;
 
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, framebuffer_info,
+      /*surface=*/nullptr, framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(true));
@@ -418,13 +412,11 @@ TEST(RasterizerTest,
   framebuffer_info.supports_readback = true;
 
   auto surface_frame1 = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, framebuffer_info,
+      /*surface=*/nullptr, framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   auto surface_frame2 = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, framebuffer_info,
+      /*surface=*/nullptr, framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled())
@@ -653,8 +645,7 @@ TEST(RasterizerTest,
   SurfaceFrame::FramebufferInfo framebuffer_info;
   framebuffer_info.supports_readback = true;
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, /*framebuffer_info=*/framebuffer_info,
+      /*surface=*/nullptr, /*framebuffer_info=*/framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(true));
@@ -713,8 +704,7 @@ TEST(
   framebuffer_info.supports_readback = true;
 
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, /*framebuffer_info=*/framebuffer_info,
+      /*surface=*/nullptr, /*framebuffer_info=*/framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(true));
@@ -774,8 +764,7 @@ TEST(
   framebuffer_info.supports_readback = true;
 
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, /*framebuffer_info=*/framebuffer_info,
+      /*surface=*/nullptr, /*framebuffer_info=*/framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(false));
@@ -834,8 +823,7 @@ TEST(
   framebuffer_info.supports_readback = true;
 
   auto surface_frame = std::make_unique<SurfaceFrame>(
-      /*surface=*/
-      nullptr, /*framebuffer_info=*/framebuffer_info,
+      /*surface=*/nullptr, /*framebuffer_info=*/framebuffer_info,
       /*submit_callback=*/[](const SurfaceFrame&, DlCanvas*) { return true; },
       /*frame_size=*/SkISize::Make(800, 600));
   EXPECT_CALL(*surface, AllowsDrawingWhenGpuDisabled()).WillOnce(Return(false));
@@ -957,8 +945,7 @@ TEST(RasterizerTest,
         SurfaceFrame::FramebufferInfo framebuffer_info;
         framebuffer_info.supports_readback = true;
         return std::make_unique<SurfaceFrame>(
-            /*surface=*/
-            nullptr, framebuffer_info,
+            /*surface=*/nullptr, framebuffer_info,
             /*submit_callback=*/
             [](const SurfaceFrame& frame, DlCanvas*) { return true; },
             /*frame_size=*/SkISize::Make(800, 600));
diff --git a/shell/common/shell_test_external_view_embedder.cc b/shell/common/shell_test_external_view_embedder.cc
index 6c87e734982c2..22b9bfe13554b 100644
--- a/shell/common/shell_test_external_view_embedder.cc
+++ b/shell/common/shell_test_external_view_embedder.cc
@@ -44,7 +44,7 @@ void ShellTestExternalViewEmbedder::BeginFrame(
     SkISize frame_size,
     GrDirectContext* context,
     double device_pixel_ratio,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   visited_platform_views_.clear();
   mutators_stacks_.clear();
   current_composition_params_.clear();
@@ -61,7 +61,7 @@ void ShellTestExternalViewEmbedder::PrerollCompositeEmbeddedView(
 
 // |ExternalViewEmbedder|
 PostPrerollResult ShellTestExternalViewEmbedder::PostPrerollAction(
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   FML_DCHECK(raster_thread_merger);
   return post_preroll_result_;
 }
@@ -73,7 +73,7 @@ void ShellTestExternalViewEmbedder::PushVisitedPlatformView(int64_t view_id) {
 
 // |ExternalViewEmbedder|
 void ShellTestExternalViewEmbedder::PushFilterToVisitedPlatformViews(
-    const std::shared_ptr<const DlImageFilter>& filter,
+    std::shared_ptr<const DlImageFilter> filter,
     const SkRect& filter_rect) {
   for (int64_t id : visited_platform_views_) {
     EmbeddedViewParams params = current_composition_params_[id];
@@ -109,7 +109,7 @@ void ShellTestExternalViewEmbedder::SubmitFrame(
 // |ExternalViewEmbedder|
 void ShellTestExternalViewEmbedder::EndFrame(
     bool should_resubmit_frame,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   end_frame_call_back_(should_resubmit_frame, raster_thread_merger);
 }
 
diff --git a/shell/common/shell_test_external_view_embedder.h b/shell/common/shell_test_external_view_embedder.h
index 93aca8578f0d3..b2e8c48d0ccf0 100644
--- a/shell/common/shell_test_external_view_embedder.h
+++ b/shell/common/shell_test_external_view_embedder.h
@@ -46,11 +46,11 @@ class ShellTestExternalViewEmbedder final : public ExternalViewEmbedder {
   void CancelFrame() override;
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override;
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   void PrerollCompositeEmbeddedView(
@@ -59,8 +59,7 @@ class ShellTestExternalViewEmbedder final : public ExternalViewEmbedder {
 
   // |ExternalViewEmbedder|
   PostPrerollResult PostPrerollAction(
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger)
-      override;
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   DlCanvas* CompositeEmbeddedView(int64_t view_id) override;
@@ -70,7 +69,7 @@ class ShellTestExternalViewEmbedder final : public ExternalViewEmbedder {
 
   // |ExternalViewEmbedder|
   void PushFilterToVisitedPlatformViews(
-      const std::shared_ptr<const DlImageFilter>& filter,
+      std::shared_ptr<const DlImageFilter> filter,
       const SkRect& filter_rect) override;
 
   // |ExternalViewEmbedder|
@@ -79,9 +78,9 @@ class ShellTestExternalViewEmbedder final : public ExternalViewEmbedder {
                    std::unique_ptr<SurfaceFrame> frame) override;
 
   // |ExternalViewEmbedder|
-  void EndFrame(bool should_resubmit_frame,
-                const fml::RefPtr<fml::RasterThreadMerger>&
-                    raster_thread_merger) override;
+  void EndFrame(
+      bool should_resubmit_frame,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   DlCanvas* GetRootCanvas() override;
diff --git a/shell/platform/android/external_view_embedder/external_view_embedder.cc b/shell/platform/android/external_view_embedder/external_view_embedder.cc
index 905c2751a3d4b..a0e516e4c10a2 100644
--- a/shell/platform/android/external_view_embedder/external_view_embedder.cc
+++ b/shell/platform/android/external_view_embedder/external_view_embedder.cc
@@ -212,7 +212,7 @@ AndroidExternalViewEmbedder::CreateSurfaceIfNeeded(GrDirectContext* context,
 
 // |ExternalViewEmbedder|
 PostPrerollResult AndroidExternalViewEmbedder::PostPrerollAction(
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   if (!FrameHasPlatformLayers()) {
     return PostPrerollResult::kSuccess;
   }
@@ -260,7 +260,7 @@ void AndroidExternalViewEmbedder::BeginFrame(
     SkISize frame_size,
     GrDirectContext* context,
     double device_pixel_ratio,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   Reset();
 
   // The surface size changed. Therefore, destroy existing surfaces as
@@ -286,7 +286,7 @@ void AndroidExternalViewEmbedder::CancelFrame() {
 // |ExternalViewEmbedder|
 void AndroidExternalViewEmbedder::EndFrame(
     bool should_resubmit_frame,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   surface_pool_->RecycleLayers();
   // JNI method must be called on the platform thread.
   if (raster_thread_merger->IsOnPlatformThread()) {
diff --git a/shell/platform/android/external_view_embedder/external_view_embedder.h b/shell/platform/android/external_view_embedder/external_view_embedder.h
index a84681ab098d5..400b43fb91a89 100644
--- a/shell/platform/android/external_view_embedder/external_view_embedder.h
+++ b/shell/platform/android/external_view_embedder/external_view_embedder.h
@@ -49,26 +49,25 @@ class AndroidExternalViewEmbedder final : public ExternalViewEmbedder {
 
   // |ExternalViewEmbedder|
   PostPrerollResult PostPrerollAction(
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger)
-      override;
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   DlCanvas* GetRootCanvas() override;
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override;
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   void CancelFrame() override;
 
   // |ExternalViewEmbedder|
-  void EndFrame(bool should_resubmit_frame,
-                const fml::RefPtr<fml::RasterThreadMerger>&
-                    raster_thread_merger) override;
+  void EndFrame(
+      bool should_resubmit_frame,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   bool SupportsDynamicThreadMerging() override;
 
diff --git a/shell/platform/darwin/ios/ios_external_view_embedder.h b/shell/platform/darwin/ios/ios_external_view_embedder.h
index 1aa67890d6117..d83b435930f21 100644
--- a/shell/platform/darwin/ios/ios_external_view_embedder.h
+++ b/shell/platform/darwin/ios/ios_external_view_embedder.h
@@ -31,11 +31,11 @@ class IOSExternalViewEmbedder : public ExternalViewEmbedder {
   void CancelFrame() override;
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override;
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   void PrerollCompositeEmbeddedView(
@@ -44,8 +44,7 @@ class IOSExternalViewEmbedder : public ExternalViewEmbedder {
 
   // |ExternalViewEmbedder|
   PostPrerollResult PostPrerollAction(
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger)
-      override;
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   DlCanvas* CompositeEmbeddedView(int64_t view_id) override;
@@ -56,16 +55,16 @@ class IOSExternalViewEmbedder : public ExternalViewEmbedder {
                    std::unique_ptr<SurfaceFrame> frame) override;
 
   // |ExternalViewEmbedder|
-  void EndFrame(bool should_resubmit_frame,
-                const fml::RefPtr<fml::RasterThreadMerger>&
-                    raster_thread_merger) override;
+  void EndFrame(
+      bool should_resubmit_frame,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   bool SupportsDynamicThreadMerging() override;
 
   // |ExternalViewEmbedder|
   void PushFilterToVisitedPlatformViews(
-      const std::shared_ptr<const DlImageFilter>& filter,
+      std::shared_ptr<const DlImageFilter> filter,
       const SkRect& filter_rect) override;
 
   // |ExternalViewEmbedder|
diff --git a/shell/platform/darwin/ios/ios_external_view_embedder.mm b/shell/platform/darwin/ios/ios_external_view_embedder.mm
index 3f4edffdd8c6f..67112e999d13d 100644
--- a/shell/platform/darwin/ios/ios_external_view_embedder.mm
+++ b/shell/platform/darwin/ios/ios_external_view_embedder.mm
@@ -34,7 +34,7 @@
     SkISize frame_size,
     GrDirectContext* context,
     double device_pixel_ratio,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   TRACE_EVENT0("flutter", "IOSExternalViewEmbedder::BeginFrame");
   FML_CHECK(platform_views_controller_);
   platform_views_controller_->BeginFrame(frame_size);
@@ -51,7 +51,7 @@
 
 // |ExternalViewEmbedder|
 PostPrerollResult IOSExternalViewEmbedder::PostPrerollAction(
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   TRACE_EVENT0("flutter", "IOSExternalViewEmbedder::PostPrerollAction");
   FML_CHECK(platform_views_controller_);
   PostPrerollResult result = platform_views_controller_->PostPrerollAction(raster_thread_merger);
@@ -77,9 +77,8 @@
 }
 
 // |ExternalViewEmbedder|
-void IOSExternalViewEmbedder::EndFrame(
-    bool should_resubmit_frame,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+void IOSExternalViewEmbedder::EndFrame(bool should_resubmit_frame,
+                                       fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   TRACE_EVENT0("flutter", "IOSExternalViewEmbedder::EndFrame");
   platform_views_controller_->EndFrame(should_resubmit_frame, raster_thread_merger);
 }
@@ -91,7 +90,7 @@
 
 // |ExternalViewEmbedder|
 void IOSExternalViewEmbedder::PushFilterToVisitedPlatformViews(
-    const std::shared_ptr<const DlImageFilter>& filter,
+    std::shared_ptr<const DlImageFilter> filter,
     const SkRect& filter_rect) {
   platform_views_controller_->PushFilterToVisitedPlatformViews(filter, filter_rect);
 }
diff --git a/shell/platform/embedder/embedder_external_view_embedder.cc b/shell/platform/embedder/embedder_external_view_embedder.cc
index 94c770f809277..ca38e86af4826 100644
--- a/shell/platform/embedder/embedder_external_view_embedder.cc
+++ b/shell/platform/embedder/embedder_external_view_embedder.cc
@@ -54,7 +54,7 @@ void EmbedderExternalViewEmbedder::BeginFrame(
     SkISize frame_size,
     GrDirectContext* context,
     double device_pixel_ratio,
-    const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger) {
+    fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) {
   Reset();
 
   pending_frame_size_ = frame_size;
diff --git a/shell/platform/embedder/embedder_external_view_embedder.h b/shell/platform/embedder/embedder_external_view_embedder.h
index 31b1f4cf6f22b..014f7393c416e 100644
--- a/shell/platform/embedder/embedder_external_view_embedder.h
+++ b/shell/platform/embedder/embedder_external_view_embedder.h
@@ -81,11 +81,11 @@ class EmbedderExternalViewEmbedder final : public ExternalViewEmbedder {
   void CancelFrame() override;
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override;
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   void PrerollCompositeEmbeddedView(
diff --git a/shell/platform/fuchsia/flutter/external_view_embedder.h b/shell/platform/fuchsia/flutter/external_view_embedder.h
index 4e5afd151ba86..a5771a9ce4bfc 100644
--- a/shell/platform/fuchsia/flutter/external_view_embedder.h
+++ b/shell/platform/fuchsia/flutter/external_view_embedder.h
@@ -68,20 +68,19 @@ class ExternalViewEmbedder final : public flutter::ExternalViewEmbedder {
 
   // |ExternalViewEmbedder|
   flutter::PostPrerollResult PostPrerollAction(
-      const fml::RefPtr<fml::RasterThreadMerger>& raster_thread_merger)
-      override;
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override;
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
-  void EndFrame(bool should_resubmit_frame,
-                const fml::RefPtr<fml::RasterThreadMerger>&
-                    raster_thread_merger) override;
+  void EndFrame(
+      bool should_resubmit_frame,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override;
 
   // |ExternalViewEmbedder|
   void SubmitFrame(GrDirectContext* context,
diff --git a/shell/platform/fuchsia/flutter/tests/platform_view_unittest.cc b/shell/platform/fuchsia/flutter/tests/platform_view_unittest.cc
index 274818de22669..f19c04ba56bc2 100644
--- a/shell/platform/fuchsia/flutter/tests/platform_view_unittest.cc
+++ b/shell/platform/fuchsia/flutter/tests/platform_view_unittest.cc
@@ -45,11 +45,11 @@ class MockExternalViewEmbedder : public flutter::ExternalViewEmbedder {
   flutter::DlCanvas* GetRootCanvas() override { return nullptr; }
 
   void CancelFrame() override {}
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override {}
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override {}
 
   void SubmitFrame(GrDirectContext* context,
                    const std::shared_ptr<impeller::AiksContext>& aiks_context,
diff --git a/shell/testing/tester_main.cc b/shell/testing/tester_main.cc
index a621dc86acf67..4be39c4d70b41 100644
--- a/shell/testing/tester_main.cc
+++ b/shell/testing/tester_main.cc
@@ -138,11 +138,11 @@ class TesterExternalViewEmbedder : public ExternalViewEmbedder {
   void CancelFrame() override {}
 
   // |ExternalViewEmbedder|
-  void BeginFrame(SkISize frame_size,
-                  GrDirectContext* context,
-                  double device_pixel_ratio,
-                  const fml::RefPtr<fml::RasterThreadMerger>&
-                      raster_thread_merger) override {}
+  void BeginFrame(
+      SkISize frame_size,
+      GrDirectContext* context,
+      double device_pixel_ratio,
+      fml::RefPtr<fml::RasterThreadMerger> raster_thread_merger) override {}
 
   // |ExternalViewEmbedder|
   void PrerollCompositeEmbeddedView(