Don't clear the dirty clip flag if it's not applied
Bug #6833979

Change-Id: I0ea78b7f31a557a335de10d910d03b0520029080
diff --git a/libs/hwui/Caches.h b/libs/hwui/Caches.h
index 5e09d94..4cbac41 100644
--- a/libs/hwui/Caches.h
+++ b/libs/hwui/Caches.h
@@ -197,15 +197,15 @@
     /**
      * Sets the scissor for the current surface.
      */
-    void setScissor(GLint x, GLint y, GLint width, GLint height);
+    bool setScissor(GLint x, GLint y, GLint width, GLint height);
 
     /**
      * Resets the scissor state.
      */
     void resetScissor();
 
-    void enableScissor();
-    void disableScissor();
+    bool enableScissor();
+    bool disableScissor();
     void setScissorEnabled(bool enabled);
 
     /**