Generate INVALID_OPERATION if feedback loops exist in CopyTex{Sub}Image2D.

gpu/command_buffer/service/framebuffer_manager.cc

 // Copyright (c) 2012 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 "gpu/command_buffer/service/framebuffer_manager.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
 #include "gpu/command_buffer/service/renderbuffer_manager.h"
 #include "gpu/command_buffer/service/texture_manager.h"
@@ skipping 108 matching lines @@
   }
 
   virtual void AddToSignature(
       TextureManager* texture_manager, std::string* signature) const override {
     DCHECK(signature);
     renderbuffer_->AddToSignature(signature);
   }
 
   virtual void OnWillRenderTo() const override {}
   virtual void OnDidRenderTo() const override {}
+  virtual bool FormsFeedbackLoop(
+      TextureRef* /* texture */, GLint /*level */) const override {
+    return false;
+  }
 
  protected:
   virtual ~RenderbufferAttachment() { }
 
  private:
   scoped_refptr<Renderbuffer> renderbuffer_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderbufferAttachment);
 };
 
@@ skipping 118 matching lines @@
   }
 
   virtual void OnWillRenderTo() const override {
     texture_ref_->texture()->OnWillModifyPixels();
   }
 
   virtual void OnDidRenderTo() const override {
     texture_ref_->texture()->OnDidModifyPixels();
   }
 
+  virtual bool FormsFeedbackLoop(
+      TextureRef* texture, GLint level) const override {
+    return texture == texture_ref_.get() && level == level_;
+  }
+
  protected:
   virtual ~TextureAttachment() {}
 
  private:
   scoped_refptr<TextureRef> texture_ref_;
   GLenum target_;
   GLint level_;
   GLsizei samples_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureAttachment);
@@ skipping 477 matching lines @@
        ++it) {
     TextureDetachObserver* observer = *it;
     observer->OnTextureRefDetachedFromFramebuffer(texture);
   }
 }
 
 }  // namespace gles2
 }  // namespace gpu