Implement AndroidTextureBuffer::NativeToI420.

talk/app/webrtc/java/jni/native_handle_impl.h

 /*
  * libjingle
  * Copyright 2015 Google Inc.
  *
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  * modification, are permitted provided that the following conditions are met:
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@@ skipping 21 matching lines @@
 #include <jni.h>
 
 #include "webrtc/common_video/include/video_frame_buffer.h"
 
 namespace webrtc_jni {
 
 // Wrapper for texture object.
 struct NativeHandleImpl {
   NativeHandleImpl(JNIEnv* jni,
                    jint j_oes_texture_id,
-                   jfloatArray j_transform_matrix);
+                   jfloatArray j_transform_matrix,
+                   jobject helper);
 
   const int oes_texture_id;
+  // Raw object pointer, relying on AndroidVideoCapturerJni to keep a

[magjed_webrtc, 2015/12/03 12:33:58]

Can't you place the |surface_texture_helper| in AndroidTextureBuffer instead?

[nisse-webrtc, 2015/12/03 13:35:21]

I can. And then the GetSurfaceHelper method is no longer needed.

I don't understand why things are divided between AndroidTextureBuffer and
NativeHandleImpl. Maybe there is, or was, a good reason.  

+  // global reference.
+  jobject surface_texture_helper;
   float sampling_matrix[16];
 };
 
 class AndroidTextureBuffer : public webrtc::NativeHandleBuffer {
  public:
   AndroidTextureBuffer(int width,
                        int height,
                        const NativeHandleImpl& native_handle,
                        const rtc::Callback0<void>& no_longer_used);
   ~AndroidTextureBuffer();
   rtc::scoped_refptr<VideoFrameBuffer> NativeToI420Buffer() override;
 
   rtc::scoped_refptr<AndroidTextureBuffer> CropAndScale(
       int cropped_input_width,
       int cropped_input_height,
       int dst_widht,
       int dst_height);
 
  private:
   NativeHandleImpl native_handle_;
   rtc::Callback0<void> no_longer_used_cb_;
 };
 
 }  // namespace webrtc_jni
 
 #endif  // TALK_APP_WEBRTC_JAVA_JNI_NATIVE_HANDLE_IMPL_H_