Android: Handle SurfaceTextureHelper ctor failure for decoder and capturer

webrtc/api/java/src/org/webrtc/VideoCapturer.java

Index: webrtc/api/java/src/org/webrtc/VideoCapturer.java
diff --git a/webrtc/api/java/src/org/webrtc/VideoCapturer.java b/webrtc/api/java/src/org/webrtc/VideoCapturer.java
index 5a515d2261f675d55bc815fa034ab63a34e279a4..f5171e65c50f9fe308b5ae9cc59ed7bff6b5345b 100644
--- a/webrtc/api/java/src/org/webrtc/VideoCapturer.java
+++ b/webrtc/api/java/src/org/webrtc/VideoCapturer.java
@@ -93,7 +93,8 @@ public interface VideoCapturer {
    * Start capturing frames in a format that is as close as possible to |width| x |height| and
    * |framerate|. If the VideoCapturer wants to deliver texture frames, it should do this by
    * rendering on the SurfaceTexture in |surfaceTextureHelper|, register itself as a listener,
-   * and forward the texture frames to CapturerObserver.onTextureFrameCaptured().
+   * and forward the texture frames to CapturerObserver.onTextureFrameCaptured(). If
+   // |surfaceTextureHelper| is null, the capturer must deliver byte buffer frames.
    */
   void startCapture(
       int width, int height, int framerate, SurfaceTextureHelper surfaceTextureHelper,