Turned the check in callWithIsac16KAndEnsureAudioIsPlaying case-insensitive.

content/test/data/media/peerconnection-call-audio.html

Index: content/test/data/media/peerconnection-call-audio.html
diff --git a/content/test/data/media/peerconnection-call-audio.html b/content/test/data/media/peerconnection-call-audio.html
index 3c996887f97a42943df0824e3809df531db2f63b..275c19ef9700093f94b63362a7233954244dad64 100644
--- a/content/test/data/media/peerconnection-call-audio.html
+++ b/content/test/data/media/peerconnection-call-audio.html
@@ -64,7 +64,7 @@
       sdp = sdp.replace(/m=audio (\d+) RTP\/SAVPF.*\r\n/g,
                         'm=audio $1 RTP/SAVPF 103 126\r\n');
       sdp = sdp.replace('a=fmtp:111 minptime=10', 'a=fmtp:103 minptime=10');
-      if (sdp.search('a=rtpmap:103 ISAC/16000') == -1)
+      if (sdp.search(/a=rtpmap:103 ISAC\/16000/i) == -1)
         failTest('Missing iSAC 16K codec on Android; cannot force codec.');
 
       return sdp;