frameworks/native: Reset dirtyRect after every queuebuffer call.

Sometimes HWR does not generate dirtyRect even when it updates the
buffer. To avoid incorrect DR calculation in such cases reset
cached dirtyRect after every queueBuffer call.

Change-Id: Iad9a2b1ecb4cf2a3789f2734a2d0e928dc56c9f0

libs/gui/Surface.cpp

@@ -331,7 +331,7 @@ int Surface::queueBuffer(android_native_buffer_t* buffer, int fenceFd) {
             &numPendingBuffers);
 
     mConsumerRunningBehind = (numPendingBuffers >= 2);
-
+    mDirtyRect.clear();
     return err;
 }