Pause expensive view updates before setting hw/sw layers.

Prevents widgets from updating mid animation.
Also pauses view updates during app close animation.

Bug: 220939231
Bug: 230617085
Bug: 226171754
Test: manual

Change-Id: I0138d57e6a7b2c22fd9a029e971b3e27c7e9f22e

src/com/android/launcher3/Launcher.java

@@ -3229,11 +3229,24 @@ public class Launcher extends StatefulActivity<LauncherState>
     public void pauseExpensiveViewUpdates() {
         // Pause page indicator animations as they lead to layer trashing.
         getWorkspace().getPageIndicator().pauseAnimations();
+
+        getWorkspace().mapOverItems((info, view) -> {
+            if (view instanceof LauncherAppWidgetHostView) {
+                ((LauncherAppWidgetHostView) view).beginDeferringUpdates();
+            }
+            return false; // Return false to continue iterating through all the items.
+        });
     }
 
     /** Resumes view updates at the end of the app launch animation. */
     public void resumeExpensiveViewUpdates() {
         getWorkspace().getPageIndicator().skipAnimationsToEnd();
-    }
 
+        getWorkspace().mapOverItems((info, view) -> {
+            if (view instanceof LauncherAppWidgetHostView) {
+                ((LauncherAppWidgetHostView) view).endDeferringUpdates();
+            }
+            return false; // Return false to continue iterating through all the items.
+        });
+    }
 }