Wire up SurfaceView stretch effect

Bug: 179047472
Test: StretchySurfaceViewActivity

Change-Id: I7f3d582cc66fb732a557e9332edc6d186db2335c
diff --git a/libs/hwui/DamageAccumulator.h b/libs/hwui/DamageAccumulator.h
index 2faa9d0..89ee0e3 100644
--- a/libs/hwui/DamageAccumulator.h
+++ b/libs/hwui/DamageAccumulator.h
@@ -35,6 +35,7 @@
 struct DirtyStack;
 class RenderNode;
 class Matrix4;
+class StretchEffect;
 
 class DamageAccumulator {
     PREVENT_COPY_AND_ASSIGN(DamageAccumulator);
@@ -62,6 +63,8 @@
 
     void finish(SkRect* totalDirty);
 
+    const StretchEffect* findNearestStretchEffect() const;
+
 private:
     void pushCommon();
     void applyMatrix4Transform(DirtyStack* frame);