Support SurfaceView synchronization.

Add API for fetching the next frame number to be produced by
a given buffer producer. Add an API to SurfaceComposer to 
defer execution of the current transaction until a given frame number. 
Together these may be used to synchronize app drawing and surface 
control updates.

Change-Id: I8e0f4993332ac0199c768c88581a453fefbaff1d
diff --git a/include/private/gui/LayerState.h b/include/private/gui/LayerState.h
index b2574d0..1711071 100644
--- a/include/private/gui/LayerState.h
+++ b/include/private/gui/LayerState.h
@@ -52,6 +52,7 @@
         eFlagsChanged               = 0x00000040,
         eLayerStackChanged          = 0x00000080,
         eCropChanged                = 0x00000100,
+        eDeferTransaction           = 0x00000200
     };
 
     layer_state_t()
@@ -87,6 +88,8 @@
             uint8_t         reserved;
             matrix22_t      matrix;
             Rect            crop;
+            sp<IBinder>     handle;
+            uint64_t        frameNumber;
             // non POD must be last. see write/read
             Region          transparentRegion;
 };