Revert of Redirect the MessageLoop's task runner to the renderer scheduler (patchset #11 id:220001 of https://codereview.chromium.org/987193002/)

Reason for revert:
Speculatively reverting.  It seems to be causing flakiness on the decodeOnOtherThread test: http://test-results.appspot.com/dashboards/flakiness_dashboard.html#testType=webkit_unit_tests&tests=decodeOnOtherThread

Original issue's description:
> Redirect the MessageLoop's task runner to the renderer scheduler
>
> Configure MessageLoop::task_runner() to post tasks through the scheduler to ensure consistent task ordering.
>
> BUG=465354
>
> Committed: https://crrev.com/f14dd762c01730a81d4a94b64ceba42eaad2d5f2
> Cr-Commit-Position: refs/heads/master@{#338706}

TBR=alexclarke@chromium.org,skyostil@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=465354

Review URL: https://codereview.chromium.org/1238483003

Cr-Commit-Position: refs/heads/master@{#338736}

5 files changed, 20 insertions, 20 deletions

diff --git a/components/scheduler/renderer/renderer_scheduler.cc b/components/scheduler/renderer/renderer_scheduler.cc
index 81f3ccb..914b802 100644
--- a/components/scheduler/renderer/renderer_scheduler.cc
+++ b/components/scheduler/renderer/renderer_scheduler.cc
@@ -8,7 +8,7 @@
 #include "base/message_loop/message_loop.h"
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_impl.h"
-#include "components/scheduler/child/scheduler_task_runner_delegate_impl.h"
+#include "components/scheduler/child/scheduler_message_loop_delegate.h"
 #include "components/scheduler/common/scheduler_switches.h"
 #include "components/scheduler/renderer/null_renderer_scheduler.h"
 #include "components/scheduler/renderer/renderer_scheduler_impl.h"
@@ -38,7 +38,7 @@ scoped_ptr<RendererScheduler> RendererScheduler::Create() {
   } else {
     base::MessageLoop* message_loop = base::MessageLoop::current();
     return make_scoped_ptr(new RendererSchedulerImpl(
-        SchedulerTaskRunnerDelegateImpl::Create(message_loop)));
+        SchedulerMessageLoopDelegate::Create(message_loop)));
   }
 }
 
diff --git a/components/scheduler/renderer/renderer_scheduler_impl.cc b/components/scheduler/renderer/renderer_scheduler_impl.cc
index a632dcf..51c51ae 100644
--- a/components/scheduler/renderer/renderer_scheduler_impl.cc
+++ b/components/scheduler/renderer/renderer_scheduler_impl.cc
@@ -9,13 +9,13 @@
 #include "base/trace_event/trace_event.h"
 #include "base/trace_event/trace_event_argument.h"
 #include "cc/output/begin_frame_args.h"
+#include "components/scheduler/child/nestable_single_thread_task_runner.h"
 #include "components/scheduler/child/prioritizing_task_queue_selector.h"
-#include "components/scheduler/child/scheduler_task_runner_delegate.h"
 
 namespace scheduler {
 
 RendererSchedulerImpl::RendererSchedulerImpl(
-    scoped_refptr<SchedulerTaskRunnerDelegate> main_task_runner)
+    scoped_refptr<NestableSingleThreadTaskRunner> main_task_runner)
     : helper_(main_task_runner,
               "renderer.scheduler",
               TRACE_DISABLED_BY_DEFAULT("renderer.scheduler"),
diff --git a/components/scheduler/renderer/renderer_scheduler_impl.h b/components/scheduler/renderer/renderer_scheduler_impl.h
index c7d4216..a6c2138 100644
--- a/components/scheduler/renderer/renderer_scheduler_impl.h
+++ b/components/scheduler/renderer/renderer_scheduler_impl.h
@@ -26,7 +26,7 @@ class SCHEDULER_EXPORT RendererSchedulerImpl : public RendererScheduler,
                                                public IdleHelper::Delegate {
  public:
   RendererSchedulerImpl(
-      scoped_refptr<SchedulerTaskRunnerDelegate> main_task_runner);
+      scoped_refptr<NestableSingleThreadTaskRunner> main_task_runner);
   ~RendererSchedulerImpl() override;
 
   // RendererScheduler implementation:
diff --git a/components/scheduler/renderer/renderer_scheduler_impl_unittest.cc b/components/scheduler/renderer/renderer_scheduler_impl_unittest.cc
index 97d8ae1..b860b19 100644
--- a/components/scheduler/renderer/renderer_scheduler_impl_unittest.cc
+++ b/components/scheduler/renderer/renderer_scheduler_impl_unittest.cc
@@ -8,8 +8,8 @@
 #include "base/test/simple_test_tick_clock.h"
 #include "cc/output/begin_frame_args.h"
 #include "cc/test/ordered_simple_task_runner.h"
-#include "components/scheduler/child/scheduler_task_runner_delegate_for_test.h"
-#include "components/scheduler/child/scheduler_task_runner_delegate_impl.h"
+#include "components/scheduler/child/nestable_task_runner_for_test.h"
+#include "components/scheduler/child/scheduler_message_loop_delegate.h"
 #include "components/scheduler/child/test_time_source.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -148,7 +148,7 @@ class RendererSchedulerImplForTest : public RendererSchedulerImpl {
   using RendererSchedulerImpl::PolicyToString;
 
   RendererSchedulerImplForTest(
-      scoped_refptr<SchedulerTaskRunnerDelegate> main_task_runner)
+      scoped_refptr<NestableSingleThreadTaskRunner> main_task_runner)
       : RendererSchedulerImpl(main_task_runner), update_policy_count_(0) {}
 
   void UpdatePolicyLocked(UpdateType update_type) override {
@@ -197,16 +197,16 @@ class RendererSchedulerImplTest : public testing::Test {
 
   void SetUp() override {
     if (message_loop_) {
-      main_task_runner_ =
-          SchedulerTaskRunnerDelegateImpl::Create(message_loop_.get());
+      nestable_task_runner_ =
+          SchedulerMessageLoopDelegate::Create(message_loop_.get());
     } else {
       mock_task_runner_ = make_scoped_refptr(
           new cc::OrderedSimpleTaskRunner(clock_.get(), false));
-      main_task_runner_ =
-          SchedulerTaskRunnerDelegateForTest::Create(mock_task_runner_);
+      nestable_task_runner_ =
+          NestableTaskRunnerForTest::Create(mock_task_runner_);
     }
-    Initialize(
-        make_scoped_ptr(new RendererSchedulerImplForTest(main_task_runner_)));
+    Initialize(make_scoped_ptr(
+        new RendererSchedulerImplForTest(nestable_task_runner_)));
   }
 
   void Initialize(scoped_ptr<RendererSchedulerImplForTest> scheduler) {
@@ -352,7 +352,7 @@ class RendererSchedulerImplTest : public testing::Test {
   scoped_refptr<cc::OrderedSimpleTaskRunner> mock_task_runner_;
   scoped_ptr<base::MessageLoop> message_loop_;
 
-  scoped_refptr<SchedulerTaskRunnerDelegate> main_task_runner_;
+  scoped_refptr<NestableSingleThreadTaskRunner> nestable_task_runner_;
   scoped_ptr<RendererSchedulerImplForTest> scheduler_;
   scoped_refptr<base::SingleThreadTaskRunner> default_task_runner_;
   scoped_refptr<base::SingleThreadTaskRunner> compositor_task_runner_;
@@ -1204,9 +1204,9 @@ class RendererSchedulerImplWithMockSchedulerTest
   void SetUp() override {
     mock_task_runner_ = make_scoped_refptr(
         new cc::OrderedSimpleTaskRunner(clock_.get(), false));
-    main_task_runner_ =
-        SchedulerTaskRunnerDelegateForTest::Create(mock_task_runner_);
-    mock_scheduler_ = new RendererSchedulerImplForTest(main_task_runner_);
+    nestable_task_runner_ =
+        NestableTaskRunnerForTest::Create(mock_task_runner_);
+    mock_scheduler_ = new RendererSchedulerImplForTest(nestable_task_runner_);
     Initialize(make_scoped_ptr(mock_scheduler_));
   }
 
diff --git a/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc b/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
index 6999da71..d67c4b4e 100644
--- a/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
+++ b/components/scheduler/renderer/webthread_impl_for_renderer_scheduler_unittest.cc
@@ -7,7 +7,7 @@
 #include "base/location.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
-#include "components/scheduler/child/scheduler_task_runner_delegate_impl.h"
+#include "components/scheduler/child/scheduler_message_loop_delegate.h"
 #include "components/scheduler/renderer/renderer_scheduler_impl.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -33,7 +33,7 @@ class MockTaskObserver : public blink::WebThread::TaskObserver {
 class WebThreadImplForRendererSchedulerTest : public testing::Test {
  public:
   WebThreadImplForRendererSchedulerTest()
-      : scheduler_(SchedulerTaskRunnerDelegateImpl::Create(&message_loop_)),
+      : scheduler_(SchedulerMessageLoopDelegate::Create(&message_loop_)),
         default_task_runner_(scheduler_.DefaultTaskRunner()),
         thread_(&scheduler_) {}