Removing useless Win7 checks + standardize its use

chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.cc

Index: chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.cc
diff --git a/chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.cc b/chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.cc
index 894f45ec8e01aecdfdbe9db56aae3b235cb101c7..cf505554b3f1723bef9a1c6cb7fb2c393a1069ea 100644
--- a/chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.cc
+++ b/chrome/browser/media/webrtc/webrtc_audio_quality_browsertest.cc
@@ -662,9 +662,9 @@ void MAYBE_WebRtcAudioQualityBrowserTest::SetupAndRecordAudioCall(
 void MAYBE_WebRtcAudioQualityBrowserTest::TestWithFakeDeviceGetUserMedia(
     const std::string& constraints,
     const std::string& perf_modifier) {
-  if (OnWin8()) {
+  if (OnWin8OrHigher()) {
     // http://crbug.com/379798.
-    LOG(ERROR) << "This test is not implemented for Windows XP/Win8.";
+    LOG(ERROR) << "This test is not implemented for Win8 or higher.";
     return;
   }
 
@@ -689,9 +689,9 @@ IN_PROC_BROWSER_TEST_F(MAYBE_WebRtcAudioQualityBrowserTest,
 IN_PROC_BROWSER_TEST_F(MAYBE_WebRtcAudioQualityBrowserTest,
                        MANUAL_TestCallQualityWithAudioFromWebAudio) {
   base::ThreadRestrictions::ScopedAllowIO allow_io;
-  if (OnWin8()) {
+  if (OnWin8OrHigher()) {
     // http://crbug.com/379798.
-    LOG(ERROR) << "This test is not implemented for Windows XP/Win8.";
+    LOG(ERROR) << "This test is not implemented for Win8 or higher.";
     return;
   }
   ASSERT_TRUE(test::HasReferenceFilesInCheckout());
@@ -764,9 +764,9 @@ void MAYBE_WebRtcAudioQualityBrowserTest::TestAutoGainControl(
     const base::FilePath::StringType& reference_filename,
     const std::string& constraints,
     const std::string& perf_modifier) {
-  if (OnWin8()) {
+  if (OnWin8OrHigher()) {
     // http://crbug.com/379798.
-    LOG(ERROR) << "This test is not implemented for Windows XP/Win8.";
+    LOG(ERROR) << "This test is not implemented for Win8 or higher.";
     return;
   }
   base::FilePath reference_file =