cc: Emulate BeginFrame in OutputSurfaces that don't support it natively

cc/trees/layer_tree_host_unittest.cc

Index: cc/trees/layer_tree_host_unittest.cc
diff --git a/cc/trees/layer_tree_host_unittest.cc b/cc/trees/layer_tree_host_unittest.cc
index 89faf4938b1d6c28b3408eae9b6d96d82549eda6..42abb830bbd4ec188616f252a81f6f042722c8f2 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -2058,10 +2058,10 @@ class LayerTreeHostTestMaxPendingFrames : public LayerTreeHostTest {
 
     const ThreadProxy* proxy = static_cast<ThreadProxy*>(host_impl->proxy());
     if (delegating_renderer()) {
-      EXPECT_EQ(1, proxy->MaxFramesPendingForTesting());
+      EXPECT_EQ(1, proxy->MaxSwapsPendingForTesting());
     } else {
       EXPECT_EQ(FrameRateController::DEFAULT_MAX_FRAMES_PENDING,
-                proxy->MaxFramesPendingForTesting());
+                proxy->MaxSwapsPendingForTesting());
     }
     EndTest();
   }
@@ -2824,7 +2824,7 @@ class LayerTreeHostTestNumFramesPending : public LayerTreeHostTest {
 
   virtual void SwapBuffersCompleteOnThread(LayerTreeHostImpl* impl) OVERRIDE {
     const ThreadProxy* proxy = static_cast<ThreadProxy*>(impl->proxy());
-    EXPECT_EQ(0, proxy->NumFramesPendingForTesting());
+    EXPECT_EQ(0, proxy->NumSwapsPendingForTesting());
   }
 
   virtual void AfterTest() OVERRIDE {}