RendererGLContext supports reparenting a GL context.

gpu/command_buffer/service/gles2_cmd_decoder.h

 // Copyright (c) 2011 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.
 
 // This file contains the GLES2Decoder class.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_DECODER_H_
 #define GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_DECODER_H_
 
 #include <vector>
@@ skipping 47 matching lines @@
   // Initializes the graphics context. Can create an offscreen
   // decoder with a frame buffer that can be referenced from the parent.
   // Takes ownership of GLContext.
   // Parameters:
   //  surface: the GL surface to render to.
   //  context: the GL context to render to.
   //  size: the size if the GL context is offscreen.
   //  allowed_extensions: A string in the same format as
   //      glGetString(GL_EXTENSIONS) that lists the extensions this context
   //      should allow. Passing NULL or "*" means allow all extensions.
-  //  parent: the GLES2 decoder that can access this decoder's front buffer
-  //      through a texture ID in its namespace.
-  //  parent_client_texture_id: the texture ID of the front buffer in the
-  //      parent's namespace.
   // Returns:
   //   true if successful.
   virtual bool Initialize(const scoped_refptr<gfx::GLSurface>& surface,
                           const scoped_refptr<gfx::GLContext>& context,
                           const gfx::Size& size,
                           const DisallowedExtensions& disallowed_extensions,
                           const char* allowed_extensions,
-                          const std::vector<int32>& attribs,
-                          GLES2Decoder* parent,
-                          uint32 parent_client_texture_id) = 0;
+                          const std::vector<int32>& attribs) = 0;
 
   // Destroys the graphics context.
   virtual void Destroy() = 0;
 
+  virtual bool SetParent(GLES2Decoder* parent_decoder,
+                         uint32 parent_texture_id) = 0;
+
   // Resize an offscreen frame buffer.
   virtual void ResizeOffscreenFrameBuffer(const gfx::Size& size) = 0;
 
   // Force the offscreen frame buffer's size to be updated. This
   // usually occurs lazily, during SwapBuffers, but on some platforms
   // (Mac OS X in particular) it must be done immediately.
   virtual bool UpdateOffscreenFrameBufferSize() = 0;
 
   // Make this decoder's GL context current.
   virtual bool MakeCurrent() = 0;
@@ skipping 33 matching lines @@
  private:
   bool debug_;
 
   DISALLOW_COPY_AND_ASSIGN(GLES2Decoder);
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_DECODER_H_