Don't let unittests access LTH from the impl thread.

cc/trees/layer_tree_host_unittest_context.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/layer_tree_host.h"
 
 #include "base/basictypes.h"
 #include "cc/layers/content_layer.h"
 #include "cc/layers/delegated_frame_provider.h"
 #include "cc/layers/delegated_frame_resource_collection.h"
@@ skipping 92 matching lines @@
       return FakeOutputSurface::Create3d(context3d.Pass());
   }
 
   DrawResult PrepareToDrawOnThread(LayerTreeHostImpl* host_impl,
                                    LayerTreeHostImpl::FrameData* frame,
                                    DrawResult draw_result) override {
     if (draw_result == DRAW_ABORTED_MISSING_HIGH_RES_CONTENT) {
       // Only valid for single-threaded impl-side painting, which activates
       // immediately and will try to draw again when content has finished.
       DCHECK(!host_impl->proxy()->HasImplThread());
-      DCHECK(layer_tree_host()->settings().impl_side_painting);
+      DCHECK(host_impl->settings().impl_side_painting);
       return draw_result;
     }
     EXPECT_EQ(DRAW_SUCCESS, draw_result);
     if (!times_to_lose_during_draw_)
       return draw_result;
 
     --times_to_lose_during_draw_;
     LoseContext();
 
     times_to_fail_create_ = times_to_fail_recreate_;
@@ skipping 752 matching lines @@
   void DidActivateTreeOnThread(LayerTreeHostImpl* host_impl) override {
     LayerTreeHostContextTest::DidActivateTreeOnThread(host_impl);
 
     FakePictureLayerImpl* root_picture = NULL;
     FakePictureLayerImpl* child_picture = NULL;
     FakePictureLayerImpl* grandchild_picture = NULL;
     FakeContentLayerImpl* root_content = NULL;
     FakeContentLayerImpl* child_content = NULL;
     FakeContentLayerImpl* grandchild_content = NULL;
 
-    if (layer_tree_host()->settings().impl_side_painting) {
+    if (host_impl->settings().impl_side_painting) {
       root_picture = static_cast<FakePictureLayerImpl*>(
           host_impl->active_tree()->root_layer());
       child_picture =
           static_cast<FakePictureLayerImpl*>(root_picture->children()[0]);
       grandchild_picture =
           static_cast<FakePictureLayerImpl*>(child_picture->children()[0]);
 
     } else {
       root_content = static_cast<FakeContentLayerImpl*>(
           host_impl->active_tree()->root_layer());
       child_content =
           static_cast<FakeContentLayerImpl*>(root_content->children()[0]);
       grandchild_content =
           static_cast<FakeContentLayerImpl*>(child_content->children()[0]);
     }
 
     ++num_commits_;
     switch (num_commits_) {
       case 1:
-        if (layer_tree_host()->settings().impl_side_painting) {
+        if (host_impl->settings().impl_side_painting) {
           EXPECT_EQ(0u, root_picture->release_resources_count());
           EXPECT_EQ(0u, child_picture->release_resources_count());
           EXPECT_EQ(0u, grandchild_picture->release_resources_count());
         } else {
           EXPECT_EQ(0u, root_content->lost_output_surface_count());
           EXPECT_EQ(0u, child_content->lost_output_surface_count());
           EXPECT_EQ(0u, grandchild_content->lost_output_surface_count());
         }
 
         // Lose the context and struggle to recreate it.
         LoseContext();
         times_to_fail_create_ = 1;
         break;
       case 2:
-        if (layer_tree_host()->settings().impl_side_painting) {
+        if (host_impl->settings().impl_side_painting) {
           EXPECT_TRUE(root_picture->release_resources_count());
           EXPECT_TRUE(child_picture->release_resources_count());
           EXPECT_TRUE(grandchild_picture->release_resources_count());
         } else {
           EXPECT_TRUE(root_content->lost_output_surface_count());
           EXPECT_TRUE(child_content->lost_output_surface_count());
           EXPECT_TRUE(grandchild_content->lost_output_surface_count());
         }
 
         EndTest();
@@ skipping 388 matching lines @@
   }
 };
 
 class UIResourceLostTestSimple : public UIResourceLostTest {
  public:
   // This is called when the commit is complete and the new layer tree has been
   // activated.
   virtual void StepCompleteOnImplThread(LayerTreeHostImpl* impl) = 0;
 
   void CommitCompleteOnThread(LayerTreeHostImpl* impl) override {
-    if (!layer_tree_host()->settings().impl_side_painting) {
+    if (!impl->settings().impl_side_painting) {
       StepCompleteOnImplThread(impl);
       PostStepCompleteToMainThread();
       ++time_step_;
     }
   }
 
   void DidActivateTreeOnThread(LayerTreeHostImpl* impl) override {
-    if (layer_tree_host()->settings().impl_side_painting) {
+    if (impl->settings().impl_side_painting) {
       StepCompleteOnImplThread(impl);
       PostStepCompleteToMainThread();
       ++time_step_;
     }
   }
 };
 
 // Losing context after an UI resource has been created.
 class UIResourceLostAfterCommit : public UIResourceLostTestSimple {
  public:
@@ skipping 443 matching lines @@
   void AfterTest() override {}
 
   bool deferred_;
 };
 
 SINGLE_AND_MULTI_THREAD_TEST_F(
     LayerTreeHostContextTestLoseAfterSendingBeginMainFrame);
 
 }  // namespace
 }  // namespace cc