Fix graphical corruption on QCOM GPU
Bug #7146141

The GL_QCOM_tiled_rendering extension requires careful use of
start/endTiling when attaching a renderbuffer dynamically.

Change-Id: I20036683ed3909ffaf40cc3d57a25257e35b6fa2
diff --git a/libs/hwui/Layer.h b/libs/hwui/Layer.h
index a551b3f..e8a85fd 100644
--- a/libs/hwui/Layer.h
+++ b/libs/hwui/Layer.h
@@ -277,6 +277,10 @@
      * Texture coordinates of the layer.
      */
     Rect texCoords;
+    /**
+     * Clipping rectangle.
+     */
+    Rect clipRect;
 
     /**
      * Dirty region indicating what parts of the layer