Revert of Fix ReadPixels from float fbo buffer in ES2/WebGL1.

ui/gl/gl_implementation.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 "ui/gl/gl_implementation.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <string>
@@ skipping 187 matching lines @@
     DCHECK(extension != NULL);
     exts.push_back(extension);
   }
   return base::JoinString(exts, " ");
 }
 
 bool WillUseGLGetStringForExtensions() {
   const char* version_str =
       reinterpret_cast<const char*>(glGetString(GL_VERSION));
   unsigned major_version, minor_version;
-  bool is_es, is_es2, is_es3;
+  bool is_es, is_es3;
   gfx::GLVersionInfo::ParseVersionString(
-      version_str, &major_version, &minor_version,
-      &is_es, &is_es2, &is_es3);
+      version_str, &major_version, &minor_version, &is_es, &is_es3);
   return is_es || major_version < 3;
 }
 
 }  // namespace gfx