Add HD browser test to WebRTC suite.

chrome/browser/media/webrtc_browsertest_common.h

Index: chrome/browser/media/webrtc_browsertest_common.h
diff --git a/chrome/browser/media/webrtc_browsertest_common.h b/chrome/browser/media/webrtc_browsertest_common.h
index 12b130d4422ed3c5c0ed3f7bd949fcf0c36492f5..0de994d68217ef294df34f1bce1efdef65f1b252 100644
--- a/chrome/browser/media/webrtc_browsertest_common.h
+++ b/chrome/browser/media/webrtc_browsertest_common.h
@@ -25,10 +25,14 @@ namespace test {
 // these sizable reference files by default.
 bool HasReferenceFilesInCheckout();
 
+// Verifies both the YUV and Y4M version of the reference file exists.
+bool HasYuvAndY4mFile(const base::FilePath::CharType* reference_file);
+
 // Retrieves the reference files dir, to which file names can be appended.
 base::FilePath GetReferenceFilesDir();
 
 extern const base::FilePath::CharType kReferenceFileName360p[];
+extern const base::FilePath::CharType kReferenceFileName720p[];
 extern const base::FilePath::CharType kYuvFileExtension[];
 extern const base::FilePath::CharType kY4mFileExtension[];