Skip DIRTY_OPAQUE optimizations when ViewRoot changes the dirty region.
Bug #3159481

Change-Id: I97d6517f4648b3efe8b13a277e0374844a4d8455
diff --git a/core/java/android/view/ViewRoot.java b/core/java/android/view/ViewRoot.java
index 17d413a..5f3184d 100644
--- a/core/java/android/view/ViewRoot.java
+++ b/core/java/android/view/ViewRoot.java
@@ -586,6 +586,9 @@
                 dirty.inset(-1, -1);
             }
         }
+        if (!mDirty.isEmpty()) {
+            mAttachInfo.mIgnoreDirtyState = true;
+        }
         mDirty.union(dirty);
         if (!mWillDrawSoon) {
             scheduleTraversals();