ozone: Allow using swiftshader with --use-gl=swiftshader.

ui/ozone/platform/cast/gl_ozone_egl_cast.h

 // Copyright 2017 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_OZONE_PLATFORM_CAST_GL_OZONE_EGL_CAST_H_
 #define UI_OZONE_PLATFORM_CAST_GL_OZONE_EGL_CAST_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 16 matching lines @@
   explicit GLOzoneEglCast(
       std::unique_ptr<chromecast::CastEglPlatform> egl_platform);
   ~GLOzoneEglCast() override;
 
   // GLOzoneEGL implementation:
   scoped_refptr<gl::GLSurface> CreateViewGLSurface(
       gfx::AcceleratedWidget widget) override;
   scoped_refptr<gl::GLSurface> CreateOffscreenGLSurface(
       const gfx::Size& size) override;
   intptr_t GetNativeDisplay() override;
-  bool LoadGLES2Bindings() override;
+  bool LoadGLES2Bindings(gl::GLImplementation implementation) override;
 
   intptr_t GetNativeWindow();
   bool ResizeDisplay(gfx::Size viewport_size);
   void ChildDestroyed();
   void TerminateDisplay();
   void ShutdownHardware();
 
   // API for keeping track of overlays per frame for logging purposes
   void OnSwapBuffers();
   void OnOverlayScheduled(const gfx::Rect& display_bounds);
@@ skipping 18 matching lines @@
   gfx::Rect overlay_bounds_;
   int previous_frame_overlay_count_ = 0;
   gfx::Rect previous_frame_overlay_bounds_;
 
   DISALLOW_COPY_AND_ASSIGN(GLOzoneEglCast);
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_CAST_GL_OZONE_EGL_CAST_H_