Thumbnail Cache - check canceled status on the right thread. am: 19797b419b

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/12029198

Change-Id: Icad59a9d583131d57cc69dbe7c72ebb0364649c9
diff --git a/quickstep/src/com/android/quickstep/TaskThumbnailCache.java b/quickstep/src/com/android/quickstep/TaskThumbnailCache.java
index ace6743..2b7a8ec 100644
--- a/quickstep/src/com/android/quickstep/TaskThumbnailCache.java
+++ b/quickstep/src/com/android/quickstep/TaskThumbnailCache.java
@@ -166,11 +166,13 @@
             public void run() {
                 ThumbnailData thumbnail = ActivityManagerWrapper.getInstance().getTaskThumbnail(
                         key.id, lowResolution);
-                if (isCanceled()) {
-                    // We don't call back to the provided callback in this case
-                    return;
-                }
+
                 MAIN_EXECUTOR.execute(() -> {
+                    if (isCanceled()) {
+                        // We don't call back to the provided callback in this case
+                        return;
+                    }
+
                     mCache.put(key, thumbnail);
                     callback.accept(thumbnail);
                     onEnd();