Pass correct parameter to `ConvertJavaStringToUTF8`.

Bug: 962428
Change-Id: Ib79b9509f96677bf5fab03e1d7110139484da785
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1609697
Commit-Queue: Rayan Kanso <rayankans@chromium.org>
Commit-Queue: Peter Beverloo <peter@chromium.org>
Auto-Submit: Rayan Kanso <rayankans@chromium.org>
Reviewed-by: Peter Beverloo <peter@chromium.org>
Reviewed-by: Richard Knoll <knollr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659007}

components/gcm_driver/gcm_driver_android.cc

@@ -85,7 +85,7 @@ void GCMDriverAndroid::OnMessageReceived(
   message.sender_id = ConvertJavaStringToUTF8(env, j_sender_id);
 
   if (!j_message_id.is_null())
-    ConvertJavaStringToUTF8(env, j_collapse_key, &message.message_id);
+    ConvertJavaStringToUTF8(env, j_message_id, &message.message_id);
   if (!j_collapse_key.is_null())
     ConvertJavaStringToUTF8(env, j_collapse_key, &message.collapse_key);