sync compositor: pass simple gfx types by const ref

See bug for reasoning

BUG=159273

Review URL: https://codereview.chromium.org/1417893006

Cr-Commit-Position: refs/heads/master@{#356653}
void AwContents::OnFindResultReceived(int active_ordinal,
                                      int match_count,
                                      bool finished) {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
  if (obj.is_null())
    return;

  Java_AwContents_onFindResultReceived(
      env, obj.obj(), active_ordinal, match_count, finished);
}

void AwContents::OnFindResultReceived(int active_ordinal,
                                      int match_count,
                                      bool finished) {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);
  JNIEnv* env = AttachCurrentThread();
  ScopedJavaLocalRef<jobject> obj = java_ref_.get(env);
  if (obj.is_null())
    return;

  Java_AwContents_onFindResultReceived(
      env, obj.obj(), active_ordinal, match_count, finished);
}
