This is initial API support required for enabling SurfaceTexture backed zero-copy for Android

ui/android/java/src/org/chromium/ui/gl/SurfaceTexturePlatformWrapper.java

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.ui.gl;
 
 import android.graphics.SurfaceTexture;
 import android.os.Build;
 import android.util.Log;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 
 /**
  * Wrapper class for the underlying platform's SurfaceTexture in order to
  * provide a stable JNI API.
  */
 @JNINamespace("gfx")
 class SurfaceTexturePlatformWrapper {
 
     private static final String TAG = "SurfaceTexturePlatformWrapper";
 
     @CalledByNative
-    private static SurfaceTexture create(int textureId) {
-        return new SurfaceTexture(textureId);
+    private static SurfaceTexture create(int textureId, boolean singleBufferMode) {
+        return new SurfaceTexture(textureId, singleBufferMode);

[reveman, 2014/03/10 16:16:58]

you'll need to add a createSingleBuffered as this doesn't work unless
"Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT"

[epennerAtGoogle, 2014/03/10 18:54:07]

Would something like this work? Unless we want more explicit names in java also.
In that case we should have two functions.

if (singleBufferMode) {
  assert(Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT);
  return new SurfaceTexture(textureId, true);
} else {
  return new SurfaceTexture(textureId);
}

[reveman, 2014/03/10 19:02:14]

It would work but I prefer if we only branch once and it happens when the client
checks the value of IsSingleBufferModeSupported(). It's a bit ugly to have an
"if (singleBufferMode)" statement in the java code when we've already done "if
(IsSingleBufferModeSupported())" in the c++ world IMO.

     }
 
     @CalledByNative
     private static void destroy(SurfaceTexture surfaceTexture) {
         surfaceTexture.setOnFrameAvailableListener(null);
         surfaceTexture.release();
     }
 
     @CalledByNative
     private static void setFrameAvailableCallback(SurfaceTexture surfaceTexture,
             long nativeSurfaceTextureListener) {
         surfaceTexture.setOnFrameAvailableListener(
                 new SurfaceTextureListener(nativeSurfaceTextureListener));
     }
 
     @CalledByNative
     private static void updateTexImage(SurfaceTexture surfaceTexture) {
         try {
             surfaceTexture.updateTexImage();
         } catch (RuntimeException e) {
             Log.e(TAG, "Error calling updateTexImage", e);
         }
     }
 
     @CalledByNative
+    private static void releaseTexImage(SurfaceTexture surfaceTexture) {
+        assert Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
+        surfaceTexture.releaseTexImage();
+    }
+
+    @CalledByNative
     private static void setDefaultBufferSize(SurfaceTexture surfaceTexture, int width,
             int height) {
         surfaceTexture.setDefaultBufferSize(width, height);
     }
 
     @CalledByNative
     private static void getTransformMatrix(SurfaceTexture surfaceTexture, float[] matrix) {
         surfaceTexture.getTransformMatrix(matrix);
     }
 
     @CalledByNative
     private static void attachToGLContext(SurfaceTexture surfaceTexture, int texName) {
         assert Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN;
         surfaceTexture.attachToGLContext(texName);
     }
 
     @CalledByNative
     private static void detachFromGLContext(SurfaceTexture surfaceTexture) {
         assert Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN;
         surfaceTexture.detachFromGLContext();
     }
 }