Revert "Accelerate the lighten blendmode if GL_EXT_blend_minmax is enabled."

cc/output/gl_renderer.h

 // Copyright 2010 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 CC_OUTPUT_GL_RENDERER_H_
 #define CC_OUTPUT_GL_RENDERER_H_
 
 #include "base/cancelable_callback.h"
 #include "cc/base/cc_export.h"
 #include "cc/base/scoped_ptr_deque.h"
@@ skipping 430 matching lines @@
   struct PendingAsyncReadPixels;
   ScopedPtrVector<PendingAsyncReadPixels> pending_async_read_pixels_;
 
   scoped_ptr<ResourceProvider::ScopedWriteLockGL> current_framebuffer_lock_;
 
   class SyncQuery;
   ScopedPtrDeque<SyncQuery> pending_sync_queries_;
   ScopedPtrDeque<SyncQuery> available_sync_queries_;
   scoped_ptr<SyncQuery> current_sync_query_;
   bool use_sync_query_;
-  bool use_blend_minmax_;
   bool use_blend_equation_advanced_;
   bool use_blend_equation_advanced_coherent_;
 
   SkBitmap on_demand_tile_raster_bitmap_;
   ResourceProvider::ResourceId on_demand_tile_raster_resource_id_;
 
   DISALLOW_COPY_AND_ASSIGN(GLRenderer);
 };
 
 // Setting DEBUG_GL_CALLS to 1 will call glGetError() after almost every GL
 // call made by the compositor. Useful for debugging rendering issues but
 // will significantly degrade performance.
 #define DEBUG_GL_CALLS 0
 
 #if DEBUG_GL_CALLS && !defined(NDEBUG)
 #define GLC(context, x)                                                        \
   (x, GLRenderer::DebugGLCall(&* context, #x, __FILE__, __LINE__))
 #else
 #define GLC(context, x) (x)
 #endif
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_GL_RENDERER_H_