Explicitly specify the ui::Compositor to DelegatedFrameHost

ui/aura/bench/bench_main.cc

Index: ui/aura/bench/bench_main.cc
diff --git a/ui/aura/bench/bench_main.cc b/ui/aura/bench/bench_main.cc
index 0ab5a736447c2d7f6cf90f9be581989b61492cdb..e2cb23e7785f0ac1d3ba2bf74889296f0b59e60d 100644
--- a/ui/aura/bench/bench_main.cc
+++ b/ui/aura/bench/bench_main.cc
@@ -94,6 +94,7 @@ class BenchCompositorObserver : public ui::CompositorObserver {
         frames_(0),
         max_frames_(max_frames) {
   }
+  virtual ~BenchCompositorObserver() {}
 
   void OnCompositingDidCommit(ui::Compositor* compositor) override {}
 
@@ -123,6 +124,8 @@ class BenchCompositorObserver : public ui::CompositorObserver {
 
   void OnCompositingLockStateChanged(Compositor* compositor) override {}
 
+  void OnCompositingShuttingDown(ui::Compositor* compositor) override {}
+
   virtual void Draw() {}
 
   int frames() const { return frames_; }