Revert of Re-enabling 720p webcam test for QTKit on Mac.

chrome/browser/media/chrome_webrtc_webcam_browsertest.cc

Index: chrome/browser/media/chrome_webrtc_webcam_browsertest.cc
diff --git a/chrome/browser/media/chrome_webrtc_webcam_browsertest.cc b/chrome/browser/media/chrome_webrtc_webcam_browsertest.cc
index e27ce24ff4ad6abc98a7dbdf85c8242b264924bd..5f4a3eaa0e66ebf3df5d83ae3bf8be04735ef8c9 100644
--- a/chrome/browser/media/chrome_webrtc_webcam_browsertest.cc
+++ b/chrome/browser/media/chrome_webrtc_webcam_browsertest.cc
@@ -97,13 +97,13 @@
             GetUserMediaAndGetStreamSize(tab, kVideoCallConstraintsVGA));
   EXPECT_EQ("640x360",
             GetUserMediaAndGetStreamSize(tab, kVideoCallConstraints360p));
-  EXPECT_EQ("1280x720",
-            GetUserMediaAndGetStreamSize(tab, kVideoCallConstraints720p));
 
-  // QTKit only supports up to 720p.
+  // QTKit supports up to 480p (used to support 720p until crbug.com/440762).
   if (IsOnQtKit())
     return;
 
+  EXPECT_EQ("1280x720",
+            GetUserMediaAndGetStreamSize(tab, kVideoCallConstraints720p));
   EXPECT_EQ("1920x1080",
             GetUserMediaAndGetStreamSize(tab, kVideoCallConstraints1080p));
 }