Cleanup various clang warnings, use unique_ptrs in several places

Change-Id: I347904b25e51fcc7de14b1e72f1acd0f6ba26f3f
diff --git a/libs/hwui/renderthread/CanvasContext.h b/libs/hwui/renderthread/CanvasContext.h
index 0cc2c7c..d7f2ebd 100644
--- a/libs/hwui/renderthread/CanvasContext.h
+++ b/libs/hwui/renderthread/CanvasContext.h
@@ -128,7 +128,7 @@
     OpenGLRenderer* mCanvas;
     bool mHaveNewSurface;
     DamageAccumulator mDamageAccumulator;
-    AnimationContext* mAnimationContext;
+    std::unique_ptr<AnimationContext> mAnimationContext;
 
     const sp<RenderNode> mRootRenderNode;