gpu: introduce DISABLE_TEXTURE_STORAGE workaround for mesa

gpu/command_buffer/service/feature_info.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/feature_info.h"
 
 #include <set>
 #include <vector>
 
 #include "base/command_line.h"
@@ skipping 803 matching lines @@
   // ES3's glTexStorage2D. We prefer support BGRA to texture storage.
   // So we don't expose GL_EXT_texture_storage when ES3 +
   // GL_EXT_texture_format_BGRA8888 because we fail the GL_BGRA8 requirement.
   // However we expose GL_EXT_texture_storage when just ES3 because we don't
   // claim to handle GL_BGRA8.
   bool support_texture_storage_on_es3 =
       (gl_version_info_->is_es3 &&
        enable_immutable_texture_format_bgra_on_es3) ||
       (gl_version_info_->is_es3 &&
        !enable_texture_format_bgra8888);
-  if (extensions.Contains("GL_EXT_texture_storage") ||
-      extensions.Contains("GL_ARB_texture_storage") ||
-      support_texture_storage_on_es3 ||
-      gl_version_info_->is_desktop_core_profile) {
+  if (!workarounds_.disable_texture_storage &&
+      (extensions.Contains("GL_EXT_texture_storage") ||
+       extensions.Contains("GL_ARB_texture_storage") ||
+       support_texture_storage_on_es3 ||
+       gl_version_info_->is_desktop_core_profile)) {
     feature_flags_.ext_texture_storage = true;
     AddExtensionString("GL_EXT_texture_storage");
     validators_.texture_parameter.AddValue(GL_TEXTURE_IMMUTABLE_FORMAT_EXT);
     if (enable_texture_format_bgra8888)
         validators_.texture_internal_format_storage.AddValue(GL_BGRA8_EXT);
     if (enable_texture_float) {
         validators_.texture_internal_format_storage.AddValue(GL_RGBA32F_EXT);
         validators_.texture_internal_format_storage.AddValue(GL_RGB32F_EXT);
         validators_.texture_internal_format_storage.AddValue(GL_ALPHA32F_EXT);
         validators_.texture_internal_format_storage.AddValue(
@@ skipping 317 matching lines @@
   if (pos == std::string::npos) {
     extensions_ += (extensions_.empty() ? "" : " ") + str;
   }
 }
 
 FeatureInfo::~FeatureInfo() {
 }
 
 }  // namespace gles2
 }  // namespace gpu