Suppress ErrorProne StringSplitter warnings

Bug: webrtc:8750
Change-Id: I1ff1bae680659f804c72eab5d14cf9c8c5046b90
Reviewed-on: https://webrtc-review.googlesource.com/39660
Commit-Queue: Oleh Prypin <oprypin@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21625}

examples/androidapp/src/org/appspot/apprtc/PeerConnectionClient.java

@@ -975,6 +975,7 @@ public class PeerConnectionClient {
     }
   }
 
+  @SuppressWarnings("StringSplitter")
   private static String setStartBitrate(
       String codec, boolean isVideoCodec, String sdpDescription, int bitrateKbps) {
     String[] lines = sdpDescription.split("\r\n");