Fix black flash when splitting task

- Draw the thumbnail view and align with the thumbnail bounds instead of
  the whole task bounds with the icon
- Defer animating the task list until after the animation completes

Bug: 73118672
Test: Enter split screen
Change-Id: Ie10c079cb22ae82f3c5974296462abae335ef5a8

src/com/android/launcher3/BaseActivity.java

@@ -98,9 +98,12 @@ public abstract class BaseActivity extends Activity {
         mDPChangeListeners.add(listener);
     }
 
+    public void removeOnDeviceProfileChangeListener(OnDeviceProfileChangeListener listener) {
+        mDPChangeListeners.remove(listener);
+    }
+
     protected void dispatchDeviceProfileChanged() {
-        int count = mDPChangeListeners.size();
-        for (int i = 0; i < count; i++) {
+        for (int i = mDPChangeListeners.size() - 1; i >= 0; i--) {
             mDPChangeListeners.get(i).onDeviceProfileChanged(mDeviceProfile);
         }
     }