VideoEncoderFallback for Android.

Expose VideoEncoderSoftwareFallbackWrapper in Java.

Bug: webrtc:7925
Change-Id: I1e1f7bc0469527f6f6a3b7051535896c3f02611c
Reviewed-on: https://webrtc-review.googlesource.com/22960
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Commit-Queue: Anders Carlsson <andersc@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#20698}

sdk/android/api/org/webrtc/VideoEncoderFallback.java

@@ -0,0 +1,22 @@
+/*
+ *  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;
+
+/**
+ * A combined video encoder that falls back on a secondary encoder if the primary encoder fails.
+ */
+public class VideoEncoderFallback extends WrappedNativeVideoEncoder {
+  public VideoEncoderFallback(VideoEncoder fallback, VideoEncoder primary) {
+    super(createNativeEncoder(fallback, primary));
+  }
+
+  private static native long createNativeEncoder(VideoEncoder fallback, VideoEncoder primary);
+}