Better backend for hardware layers.

With this new backend, a hardware layer is only recreated when
its associated view is udpated. This offers fast composition
in GL and fast update of the layer in GL as well.

Change-Id: I97c43a612f5955c6bf1c192c8ca4af10fdf1d076
diff --git a/libs/hwui/OpenGLRenderer.h b/libs/hwui/OpenGLRenderer.h
index 8f93f5b..5f45915 100644
--- a/libs/hwui/OpenGLRenderer.h
+++ b/libs/hwui/OpenGLRenderer.h
@@ -64,6 +64,10 @@
     virtual void prepare(bool opaque);
     virtual void finish();
 
+    // These two calls must not be recorded in display lists
+    void interrupt();
+    void resume();
+
     virtual void acquireContext();
     virtual void releaseContext();
 
@@ -91,6 +95,8 @@
     virtual bool clipRect(float left, float top, float right, float bottom, SkRegion::Op op);
 
     virtual void drawDisplayList(DisplayList* displayList);
+    virtual void drawLayer(int texture, float left, float top, float right, float bottom,
+            float u, float v, SkPaint* paint);
     virtual void drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint);
     virtual void drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint);
     virtual void drawBitmap(SkBitmap* bitmap, float srcLeft, float srcTop,