Prevent race condition while switching surfaces (flutter#24838)

Author: Emmanuel Garcia

shell/platform/android/io/flutter/embedding/android/FlutterImageView.java

@@ -118,9 +118,6 @@ public FlutterRenderer getAttachedRenderer() {
    */
   @Override
   public void attachToRenderer(@NonNull FlutterRenderer flutterRenderer) {
-    if (isAttachedToFlutterRenderer) {
-      return;
-    }
     switch (kind) {
       case background:
         flutterRenderer.swapSurface(imageReader.getSurface());

shell/platform/android/io/flutter/embedding/android/FlutterView.java

@@ -1068,7 +1068,9 @@ public void revertImageView(@NonNull Runnable onDone) {
           public void onFlutterUiDisplayed() {
             renderer.removeIsDisplayingFlutterUiListener(this);
             onDone.run();
-            flutterImageView.detachFromRenderer();
+            if (!(renderSurface instanceof FlutterImageView)) {
+              flutterImageView.detachFromRenderer();
+            }
           }
 
           @Override