Add a YUV444 color format test for VP9.

content/browser/media/media_browsertest.cc

Index: content/browser/media/media_browsertest.cc
diff --git a/content/browser/media/media_browsertest.cc b/content/browser/media/media_browsertest.cc
index db3bd2521a910e68ecba34720bc39600095ca504..254a7447c4f0119f761ca80203093f9a7efe2b03 100644
--- a/content/browser/media/media_browsertest.cc
+++ b/content/browser/media/media_browsertest.cc
@@ -224,6 +224,10 @@ IN_PROC_BROWSER_TEST_F(MediaTest, MAYBE(Yuv420pVp8)) {
   RunColorFormatTest("yuv420p.webm", "ENDED");
 }
 
+IN_PROC_BROWSER_TEST_F(MediaTest, MAYBE(Yuv444pVp9)) {
+  RunColorFormatTest("yuv444p.webm", "ENDED");
+}
+
 #if defined(USE_PROPRIETARY_CODECS)
 IN_PROC_BROWSER_TEST_F(MediaTest, MAYBE(Yuv420pH264)) {
   RunColorFormatTest("yuv420p.mp4", "ENDED");