Android: Add helper function for converting Integer -> rtc::Optional<int>

Bug: webrtc:8278
Change-Id: I1c499a35c5fd77304ed2906ea61ef2322ec98cea
No-Tree-Checks: true
Reviewed-on: https://webrtc-review.googlesource.com/20876
Commit-Queue: Magnus Jedvert <magjed@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20750}

sdk/android/src/java/org/webrtc/IntegerWrapper.java

@@ -0,0 +1,24 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+package org.webrtc;
+
+/** This class contains the Java glue code for JNI generation of Integer handling. */
+class IntegerWrapper {
+  @CalledByNative
+  static Integer create(int i) {
+    return Integer.valueOf(i);
+  }
+
+  @CalledByNative
+  static int getIntValue(Integer i) {
+    return i;
+  }
+}

sdk/android/src/java/org/webrtc/VideoEncoderWrapper.java

@@ -61,11 +61,6 @@ class VideoEncoderWrapper {
     return scalingSettings.high;
   }
 
-  @CalledByNative
-  static int getIntValue(Integer i) {
-    return i.intValue();
-  }
-
   @CalledByNative
   static VideoEncoder.Callback createEncoderCallback(final long nativeEncoder) {
     return (EncodedImage frame, VideoEncoder.CodecSpecificInfo info)