Add video pixel tests for DirectComposition layers.

content/test/gpu/gpu_tests/pixel_test_pages.py

Index: content/test/gpu/gpu_tests/pixel_test_pages.py
diff --git a/content/test/gpu/gpu_tests/pixel_test_pages.py b/content/test/gpu/gpu_tests/pixel_test_pages.py
index 4046f2b628780e9666692b064011d877d46ea30b..acc4009648bf4e0846056f5e5cacb49b4b696177 100644
--- a/content/test/gpu/gpu_tests/pixel_test_pages.py
+++ b/content/test/gpu/gpu_tests/pixel_test_pages.py
@@ -487,3 +487,21 @@ def MacSpecificPages(base_name):
       tolerance=10,
       browser_args=['--disable-mac-overlays']),
   ]
+
+def DirectCompositionPages(base_name):
+  browser_args = ['--enable-direct-composition-layers']
+  return [
+    PixelTestPage(
+      'pixel_video_mp4.html',
+      base_name + '_DirectComposition_Video_MP4',
+      test_rect=[0, 0, 300, 300],
+      revision=1,
+      browser_args=browser_args),
+
+    PixelTestPage(
+      'pixel_video_vp9.html',
+      base_name + '_DirectComposition_Video_VP9',
+      test_rect=[0, 0, 300, 300],
+      revision=1,
+      browser_args=browser_args),
+  ]