views/mus: Install a mus-friend ContextFactory for tests.

ui/compositor/compositor_unittest.cc

Index: ui/compositor/compositor_unittest.cc
diff --git a/ui/compositor/compositor_unittest.cc b/ui/compositor/compositor_unittest.cc
index 9b34e423d6cd44659b09a4142803f173b8dcd6ef..e62e0b8c430a84131a25aeb4a6c3ee619a3eab11 100644
--- a/ui/compositor/compositor_unittest.cc
+++ b/ui/compositor/compositor_unittest.cc
@@ -26,40 +26,6 @@ using testing::_;
 namespace ui {
 namespace {
 
-class FakeCompositorFrameSink : public cc::SurfaceFactoryClient {
- public:
-  FakeCompositorFrameSink(const cc::FrameSinkId& frame_sink_id,
-                          cc::SurfaceManager* manager)
-      : frame_sink_id_(frame_sink_id),
-        manager_(manager),
-        source_(nullptr),
-        factory_(frame_sink_id, manager, this) {
-    manager_->RegisterFrameSinkId(frame_sink_id_);
-    manager_->RegisterSurfaceFactoryClient(frame_sink_id_, this);
-  }
-
-  ~FakeCompositorFrameSink() override {
-    manager_->UnregisterSurfaceFactoryClient(frame_sink_id_);
-    manager_->InvalidateFrameSinkId(frame_sink_id_);
-  }
-
-  void ReturnResources(const cc::ReturnedResourceArray& resources) override {}
-  void SetBeginFrameSource(cc::BeginFrameSource* begin_frame_source) override {
-    DCHECK(!source_ || !begin_frame_source);
-    source_ = begin_frame_source;
-  };
-
- private:
-  const cc::FrameSinkId frame_sink_id_;
-  cc::SurfaceManager* const manager_;
-  cc::BeginFrameSource* source_;
-  cc::SurfaceFactory factory_;
-};
-
-ACTION_P2(RemoveObserver, compositor, observer) {
-  compositor->RemoveBeginFrameObserver(observer);
-}
-
 // Test fixture for tests that require a ui::Compositor with a real task
 // runner.
 class CompositorTest : public testing::Test {