Fix rendering artifacts on tiled renderers
Bug #7275145

This change fixes ViewRoot and adds extra debug information. It does
not solve the problem entirely. Another CL will.

Change-Id: I7e604ba38aad7f421769783dcbd998d6905ab2d9
diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index 2d083b6..ae51c1d 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -2904,6 +2904,7 @@
      */
     int mOldHeightMeasureSpec = Integer.MIN_VALUE;
 
+    @ViewDebug.ExportedProperty(deepExport = true, prefix = "bg_")
     private Drawable mBackground;
 
     private int mBackgroundResource;