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

ui/gl/android/surface_texture.cc

 // 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.
 
 #include "ui/gl/android/surface_texture.h"
 
 #include <android/native_window_jni.h>
 
 // TODO(boliu): Remove this include when we move off ICS.
 #include "base/android/build_info.h"
 #include "base/android/jni_android.h"
 #include "base/logging.h"
 #include "jni/SurfaceTexturePlatformWrapper_jni.h"
 #include "ui/gl/android/scoped_java_surface.h"
 #include "ui/gl/android/surface_texture_listener.h"
 #include "ui/gl/gl_bindings.h"
 
 // TODO(boliu): Remove this method when when we move off ICS. See
 // http://crbug.com/161864.
 bool GlContextMethodsAvailable() {
   bool available = base::android::BuildInfo::GetInstance()->sdk_int() >= 16;
   if (!available)
     LOG(WARNING) << "Running on unsupported device: rendering may not work";
   return available;
 }
 
 namespace gfx {
 
-SurfaceTexture::SurfaceTexture(int texture_id) {
+SurfaceTexture* SurfaceTexture::Create(int texture_id) {
+  return new SurfaceTexture(texture_id, false);
+}
+
+SurfaceTexture* SurfaceTexture::CreateSingleBufferMode(int texture_id) {
+  DCHECK(IsSingleBufferModeSupported());
+  return new SurfaceTexture(texture_id, true);
+}
+
+SurfaceTexture::SurfaceTexture(int texture_id, bool single_buffer_mode) {
   JNIEnv* env = base::android::AttachCurrentThread();
-  j_surface_texture_.Reset(
-      Java_SurfaceTexturePlatformWrapper_create(env, texture_id));
+  j_surface_texture_.Reset(Java_SurfaceTexturePlatformWrapper_create(
+      env, texture_id, single_buffer_mode));
 }
 
 SurfaceTexture::~SurfaceTexture() {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_SurfaceTexturePlatformWrapper_destroy(env, j_surface_texture_.obj());
 }
 
 void SurfaceTexture::SetFrameAvailableCallback(
     const base::Closure& callback) {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_SurfaceTexturePlatformWrapper_setFrameAvailableCallback(
       env,
       j_surface_texture_.obj(),
       reinterpret_cast<intptr_t>(new SurfaceTextureListener(callback)));
 }
 
 void SurfaceTexture::UpdateTexImage() {
   JNIEnv* env = base::android::AttachCurrentThread();
   Java_SurfaceTexturePlatformWrapper_updateTexImage(env,
                                                     j_surface_texture_.obj());
 }
 
+void SurfaceTexture::ReleaseTexImage() {
+  DCHECK(IsSingleBufferModeSupported());
+  JNIEnv* env = base::android::AttachCurrentThread();
+  Java_SurfaceTexturePlatformWrapper_releaseTexImage(env,
+                                                     j_surface_texture_.obj());
+}
+
 void SurfaceTexture::GetTransformMatrix(float mtx[16]) {
   JNIEnv* env = base::android::AttachCurrentThread();
 
   base::android::ScopedJavaLocalRef<jfloatArray> jmatrix(
       env, env->NewFloatArray(16));
   Java_SurfaceTexturePlatformWrapper_getTransformMatrix(
       env, j_surface_texture_.obj(), jmatrix.obj());
 
   jboolean is_copy;
   jfloat* elements = env->GetFloatArrayElements(jmatrix.obj(), &is_copy);
@@ skipping 37 matching lines @@
 
 ANativeWindow* SurfaceTexture::CreateSurface() {
   JNIEnv* env = base::android::AttachCurrentThread();
   ScopedJavaSurface surface(this);
   ANativeWindow* native_window = ANativeWindow_fromSurface(
       env, surface.j_surface().obj());
   return native_window;
 }
 
 // static
+bool SurfaceTexture::IsSingleBufferModeSupported() {
+  return base::android::BuildInfo::GetInstance()->sdk_int() >= 19;
+}
+
 bool SurfaceTexture::RegisterSurfaceTexture(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace gfx