cc: Split Proxy and TaskRunnerProvider for the LayerTreeHost

cc/trees/threaded_channel_unittest.cc

Index: cc/trees/threaded_channel_unittest.cc
diff --git a/cc/trees/threaded_channel_unittest.cc b/cc/trees/threaded_channel_unittest.cc
index 6371f781393860231efac45a1e77021a594df58c..e9b6d5141f0f718aaa34bec84f8b8a52c98148a7 100644
--- a/cc/trees/threaded_channel_unittest.cc
+++ b/cc/trees/threaded_channel_unittest.cc
@@ -30,7 +30,9 @@ class ThreadedChannelTest : public LayerTreeTest {
                               base::Unretained(this)));
   }
 
-  virtual void StartTestOnImplThread() { DCHECK(proxy()->IsImplThread()); }
+  virtual void StartTestOnImplThread() {
+    DCHECK(task_runner_provider()->IsImplThread());
+  }
 
   void AfterTest() override {}