fix(android): new arch ProGuard (#108)

* fix(android): new arch proguard

* fix: proguard

* fix: **

packages/react-native/android/proguard-rules.pro

@@ -1,22 +1,15 @@
-# Add project specific ProGuard rules here.
-# By default, the flags in this file are appended to flags specified
-# in /usr/local/Cellar/android-sdk/24.3.3/tools/proguard/proguard-android.txt
-# You can edit the include path and order by changing the proguardFiles
-# directive in build.gradle.
-#
-# For more details, see
-#   http://developer.android.com/guide/developing/tools/proguard.html
-
-# Add any project specific keep options here:
-
-# If your project uses WebView with JS, uncomment the following
-# and specify the fully qualified class name to the JavaScript interface
-# class:
-#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
-#   public *;
-#}
-
+# Old Architecture
 # Invoked via reflection, when setting js bundle.
 -keepclassmembers class com.facebook.react.ReactInstanceManager {
     private final ** mBundleLoader;
+}
+
+# New Architecture
+# Keep fields accessed via reflection in ReactHost
+-keepclassmembers class com.facebook.react.runtime.ReactHostImpl {
+    private final ** mReactHostDelegate;
+}
+
+-keepclassmembers class * implements com.facebook.react.runtime.ReactHostDelegate {
+    ** jsBundleLoader;
 }