cc: Split Proxy and TaskRunnerProvider for the LayerTreeHost

The LayerTreeHost uses the abstract part of Proxy to access the impl
side of the compositor and the TaskRunnerProvider to access the main
task runner and assertion checks.
Decoupling these 2 will allow the LayerTreeHost used only for
deserialization and commits on the client to be built without a proxy.

This is a follow-up patch to: https://codereview.chromium.org/1418953002/

BUG=527200
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1419283002

Cr-Commit-Position: refs/heads/master@{#359196}

1 files changed, 9 insertions, 3 deletions

diff --git a/cc/test/layer_tree_test.h b/cc/test/layer_tree_test.h
index 33593aa..0c2dfb1 100644
--- a/cc/test/layer_tree_test.h
+++ b/cc/test/layer_tree_test.h
@@ -253,9 +253,11 @@ class LayerTreeTest : public testing::Test, public TestHooks {
 
   bool HasImplThread() { return !!impl_thread_; }
   base::SingleThreadTaskRunner* ImplThreadTaskRunner() {
-    DCHECK(proxy());
-    return proxy()->ImplThreadTaskRunner() ? proxy()->ImplThreadTaskRunner()
-                                           : main_task_runner_.get();
+    DCHECK(task_runner_provider());
+    base::SingleThreadTaskRunner* impl_thread_task_runner =
+        task_runner_provider()->ImplThreadTaskRunner();
+    return impl_thread_task_runner ? impl_thread_task_runner
+                                   : main_task_runner_.get();
   }
   base::SingleThreadTaskRunner* MainThreadTaskRunner() {
     return main_task_runner_.get();
@@ -263,6 +265,10 @@ class LayerTreeTest : public testing::Test, public TestHooks {
   Proxy* proxy() const {
     return layer_tree_host_ ? layer_tree_host_->proxy() : NULL;
   }
+  TaskRunnerProvider* task_runner_provider() const {
+    return layer_tree_host_ ? layer_tree_host_->task_runner_provider()
+                            : nullptr;
+  }
   TaskGraphRunner* task_graph_runner() const {
     return task_graph_runner_.get();
   }