Reland of Add isnan() workaround for Intel Mac

gpu/command_buffer/service/gles2_cmd_decoder.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/gles2_cmd_decoder.h"
 
 #include <limits.h>
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
@@ skipping 3746 matching lines @@
   if (workarounds().remove_pow_with_constant_exponent)
     driver_bug_workarounds |= SH_REMOVE_POW_WITH_CONSTANT_EXPONENT;
   if (workarounds().emulate_abs_int_function)
     driver_bug_workarounds |= SH_EMULATE_ABS_INT_FUNCTION;
   if (workarounds().rewrite_texelfetchoffset_to_texelfetch)
     driver_bug_workarounds |= SH_REWRITE_TEXELFETCHOFFSET_TO_TEXELFETCH;
   if (workarounds().add_and_true_to_loop_condition)
     driver_bug_workarounds |= SH_ADD_AND_TRUE_TO_LOOP_CONDITION;
   if (workarounds().rewrite_do_while_loops)
     driver_bug_workarounds |= SH_REWRITE_DO_WHILE_LOOPS;
+  if (workarounds().emulate_isnan_on_float)
+    driver_bug_workarounds |= SH_EMULATE_ISNAN_FLOAT_FUNCTION;
 
   resources.WEBGL_debug_shader_precision =
       group_->gpu_preferences().emulate_shader_precision;
 
   ShShaderOutput shader_output_language =
       ShaderTranslator::GetShaderOutputLanguageForContext(gl_version_info());
 
   vertex_translator_ = shader_translator_cache()->GetTranslator(
       GL_VERTEX_SHADER, shader_spec, &resources, shader_output_language,
       driver_bug_workarounds);
@@ skipping 14468 matching lines @@
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "base/macros.h"
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu