Disable flaky WebRtcGetUserMediaBrowserTest.TestGetUserMediaAspectRatio16To9

TBR=guidou@chromium.org

Bug: 846582
Change-Id: I9d56948be36ff8b672f41fece3e028f2bae0de2f
Reviewed-on: https://chromium-review.googlesource.com/1073110Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Trent Apted <tapted@chromium.org>
Cr-Commit-Position: refs/heads/master@{#561790}

content/browser/webrtc/webrtc_getusermedia_browsertest.cc

@@ -539,8 +539,9 @@ IN_PROC_BROWSER_TEST_P(WebRtcGetUserMediaBrowserTest,
 }
 
 // This test calls getUserMedia and checks for aspect ratio behavior.
+// Flaky: crbug.com/846582.
 IN_PROC_BROWSER_TEST_P(WebRtcGetUserMediaBrowserTest,
-                       TestGetUserMediaAspectRatio16To9) {
+                       DISABLED_TestGetUserMediaAspectRatio16To9) {
   ASSERT_TRUE(embedded_test_server()->Start());
 
   GURL url(embedded_test_server()->GetURL("/media/getusermedia.html"));