fix(paginator): change class name of increment and decrement icons

Fix such that the previous page navigation button contains an icon with class decrement,
and the next page navigation button contains an icon with class increment. Previously
they were incorrectly swapped.

Noticed during fix for #9278

src/lib/paginator/_paginator-theme.scss

@@ -16,15 +16,15 @@
     color: mat-color($foreground, secondary-text);
   }
 
-  .mat-paginator-increment,
-  .mat-paginator-decrement {
+  .mat-paginator-decrement,
+  .mat-paginator-increment {
     border-top: 2px solid mat-color($foreground, 'icon');
     border-right: 2px solid mat-color($foreground, 'icon');
   }
 
   .mat-icon-button[disabled] {
-    .mat-paginator-increment,
-    .mat-paginator-decrement {
+    .mat-paginator-decrement,
+    .mat-paginator-increment {
       border-color: mat-color($foreground, 'disabled');
     }
   }

src/lib/paginator/paginator.html

@@ -32,7 +32,7 @@
             [matTooltip]="_intl.previousPageLabel"
             [matTooltipPosition]="'above'"
             [disabled]="!hasPreviousPage()">
-      <div class="mat-paginator-increment"></div>
+      <div class="mat-paginator-decrement"></div>
     </button>
     <button mat-icon-button type="button"
             class="mat-paginator-navigation-next"
@@ -41,7 +41,7 @@
             [matTooltip]="_intl.nextPageLabel"
             [matTooltipPosition]="'above'"
             [disabled]="!hasNextPage()">
-      <div class="mat-paginator-decrement"></div>
+      <div class="mat-paginator-increment"></div>
     </button>
   </div>
 </div>

src/lib/paginator/paginator.scss

@@ -50,37 +50,37 @@ $mat-paginator-button-increment-icon-margin: 16px;
   margin: $mat-paginator-range-label-margin;
 }
 
-.mat-paginator-increment-button + .mat-paginator-increment-button {
+.mat-paginator-decrement-button + .mat-paginator-decrement-button {
   margin: 0 0 0 $mat-paginator-button-margin;
 
   [dir='rtl'] & {
     margin: 0 $mat-paginator-button-margin 0 0;
   }
 }
 
-.mat-paginator-increment,
-.mat-paginator-decrement {
+.mat-paginator-decrement,
+.mat-paginator-increment {
   width: $mat-paginator-button-icon-width;
   height: $mat-paginator-button-icon-height;
 }
 
-.mat-paginator-decrement,
-[dir='rtl'] .mat-paginator-increment {
-  transform: rotate(45deg);
-}
 .mat-paginator-increment,
 [dir='rtl'] .mat-paginator-decrement {
+  transform: rotate(45deg);
+}
+.mat-paginator-decrement,
+[dir='rtl'] .mat-paginator-increment {
   transform: rotate(225deg);
 }
 
-.mat-paginator-decrement {
+.mat-paginator-increment {
   margin-left: $mat-paginator-button-decrement-icon-margin;
   [dir='rtl'] & {
     margin-right: $mat-paginator-button-decrement-icon-margin;
   }
 }
 
-.mat-paginator-increment {
+.mat-paginator-decrement {
   margin-left: $mat-paginator-button-increment-icon-margin;
   [dir='rtl'] & {
     margin-right: $mat-paginator-button-increment-icon-margin;