Update from chromium https://crrev.com/302282

cc/test/layer_tree_pixel_test.h

Index: cc/test/layer_tree_pixel_test.h
diff --git a/cc/test/layer_tree_pixel_test.h b/cc/test/layer_tree_pixel_test.h
index e6f5cb7a47e7a5d9049423740a351cbe755a3cd5..c3c324af37fd9872fe8df04b843d096d7df20ca6 100644
--- a/cc/test/layer_tree_pixel_test.h
+++ b/cc/test/layer_tree_pixel_test.h
@@ -30,6 +30,12 @@ class TextureLayer;
 class TextureMailbox;
 
 class LayerTreePixelTest : public LayerTreeTest {
+ public:
+  enum PixelTestType {
+    PIXEL_TEST_GL,
+    PIXEL_TEST_SOFTWARE,
+  };
+
  protected:
   LayerTreePixelTest();
   virtual ~LayerTreePixelTest();
@@ -58,15 +64,14 @@ class LayerTreePixelTest : public LayerTreeTest {
   scoped_refptr<TextureLayer> CreateTextureLayer(const gfx::Rect& rect,
                                                  const SkBitmap& bitmap);
 
-  enum PixelTestType {
-    PIXEL_TEST_GL,
-    PIXEL_TEST_SOFTWARE,
-  };
-
   void RunPixelTest(PixelTestType type,
                     scoped_refptr<Layer> content_root,
                     base::FilePath file_name);
 
+  void RunSingleThreadedPixelTest(PixelTestType test_type,
+                                  scoped_refptr<Layer> content_root,
+                                  base::FilePath file_name);
+
   void RunPixelTestWithReadbackTarget(PixelTestType type,
                                       scoped_refptr<Layer> content_root,
                                       Layer* target,