Support single-threaded impl-side painting

cc/test/layer_tree_pixel_test.cc

 // Copyright 2013 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/test/layer_tree_pixel_test.h"
 
 #include "base/command_line.h"
 #include "base/path_service.h"
 #include "cc/base/switches.h"
 #include "cc/layers/solid_color_layer.h"
@@ skipping 179 matching lines @@
 }
 
 void LayerTreePixelTest::RunPixelTest(
     PixelTestType test_type,
     scoped_refptr<Layer> content_root,
     base::FilePath file_name) {
   test_type_ = test_type;
   content_root_ = content_root;
   readback_target_ = NULL;
   ref_file_ = file_name;
-  RunTest(true, false, impl_side_painting_);
+  bool threaded = true;
+  RunTest(threaded, false, impl_side_painting_);
+}
+
+void LayerTreePixelTest::RunSingleThreadedPixelTest(
+    PixelTestType test_type,
+    scoped_refptr<Layer> content_root,
+    base::FilePath file_name) {
+  test_type_ = test_type;
+  content_root_ = content_root;
+  readback_target_ = NULL;
+  ref_file_ = file_name;
+  bool threaded = false;
+  RunTest(threaded, false, impl_side_painting_);
 }
 
 void LayerTreePixelTest::RunPixelTestWithReadbackTarget(
     PixelTestType test_type,
     scoped_refptr<Layer> content_root,
     Layer* target,
     base::FilePath file_name) {
   test_type_ = test_type;
   content_root_ = content_root;
   readback_target_ = target;
@@ skipping 147 matching lines @@
 
   *texture_mailbox = TextureMailbox(mailbox, GL_TEXTURE_2D, sync_point);
   *release_callback = SingleReleaseCallback::Create(
       base::Bind(&LayerTreePixelTest::ReleaseTextureMailbox,
                  base::Unretained(this),
                  base::Passed(&context),
                  texture_id));
 }
 
 }  // namespace cc