Make OSMesa GL implementation advertise supported functionality as ES2 extensions

ui/gfx/gl/gl_implementation.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.
 
 #ifndef UI_GFX_GL_GL_IMPLEMENTATION_H_
 #define UI_GFX_GL_GL_IMPLEMENTATION_H_
 #pragma once
 
 #include <string>
 
@@ skipping 24 matching lines @@
 
 // Initialize Debug logging wrappers for GL bindings.
 void InitializeDebugGLBindings();
 
 // Set the current GL implementation.
 void SetGLImplementation(GLImplementation implementation);
 
 // Get the current GL implementation.
 GL_EXPORT GLImplementation GetGLImplementation();
 
+// Does the underlying GL support all features from Desktop GL 2.0 that were
+// removed from the ES 2.0 spec without requiring specific extension strings.
+GL_EXPORT bool HasDesktopGLFeatures();
+
 // Get the GL implementation with a given name.
 GLImplementation GetNamedGLImplementation(const std::wstring& name);
 
 // Get the name of a GL implementation.
 const char* GetGLImplementationName(GLImplementation implementation);
 
 // Initialize the preferred GL binding from the given list. The preferred GL
 // bindings depend on command line switches passed by the user and which GL
 // implementation is the default on a given platform.
 bool InitializeRequestedGLBindings(
     const GLImplementation* allowed_implementations_begin,
     const GLImplementation* allowed_implementations_end,
     GLImplementation default_implementation);
 
 // Add a native library to those searched for GL entry points.
 void AddGLNativeLibrary(base::NativeLibrary library);
 
 // Set an additional function that will be called to find GL entry points.
 void SetGLGetProcAddressProc(GLGetProcAddressProc proc);
 
 // Find an entry point in the current GL implementation.
 void* GetGLProcAddress(const char* name);
 
 }  // namespace gfx
 
 #endif  // UI_GFX_GL_GL_IMPLEMENTATION_H_