Fix onKeyAdded check causing flakiness in the tests, and enabling relevant disabled test.

BUG=168252


Review URL: https://chromiumcodereview.appspot.com/11753017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@175113 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/encrypted_media_browsertest.cc

@@ -129,7 +129,7 @@ IN_PROC_BROWSER_TEST_F(EncryptedMediaTest, InvalidKeySystem) {
                          "com.example.invalid", kExpected));
 }
 
-IN_PROC_BROWSER_TEST_P(EncryptedMediaTest, DISABLED_BasicPlayback_AudioOnly) {
+IN_PROC_BROWSER_TEST_P(EncryptedMediaTest, BasicPlayback_AudioOnly) {
   const string16 kExpected = ASCIIToUTF16("ENDED");
   ASSERT_NO_FATAL_FAILURE(
       TestSimplePlayback("bear-a-enc_a.webm", kWebMAudioOnly,

content/test/data/media/encrypted_media_player.html

@@ -10,11 +10,12 @@
       var video = document.querySelector('video');
 
       function onTimeUpdate() {
-        // webkitkeyadded should have been fired before playback.
-        if (!video.receivedKeyAdded)
-          failTest('Key added event not received.');
         if (video.currentTime < 1)
           return;
+        // keyadded may be fired around the start of playback; check for it
+        // after a delay to avoid timing issues.
+        if (!video.receivedKeyAdded)
+          failTest('Key added event not received.');
         if (video.isHeartbeatExpected && !video.receivedHeartbeat)
           failTest('Heartbeat keymessage event not received.');
         video.removeEventListener('ended', failTest);