Implemented failIfMajorPerformanceCaveat WebGL context creation attribute.

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 <stdio.h>
 
 #include <algorithm>
 #include <list>
@@ skipping 2197 matching lines @@
 
   compile_shader_always_succeeds_ = CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kCompileShaderAlwaysSucceeds);
 
 
   // Take ownership of the context and surface. The surface can be replaced with
   // SetSurface.
   context_ = context;
   surface_ = surface;
 
+  ContextCreationAttribHelper attrib_parser;
+  if (!attrib_parser.Parse(attribs))
+    return false;
+
+  // If the failIfMajorPerformanceCaveat context creation attribute was true
+  // and we are using a software renderer, fail.
+  if (attrib_parser.fail_if_major_perf_caveat_ &&
+      feature_info_->feature_flags().is_swiftshader) {
+    group_ = NULL;  // Must not destroy ContextGroup if it is not initialized.
+    Destroy(true);
+    return false;
+  }
+
   if (!group_->Initialize(this, disallowed_features)) {
     LOG(ERROR) << "GpuScheduler::InitializeCommon failed because group "
                << "failed to initialize.";
     group_ = NULL;  // Must not destroy ContextGroup if it is not initialized.
     Destroy(true);
     return false;
   }
   CHECK_GL_ERROR();
 
   disallowed_features_ = disallowed_features;
@@ skipping 42 matching lines @@
     ref = texture_manager()->GetDefaultTextureInfo(GL_TEXTURE_CUBE_MAP);
     state_.texture_units[tt].bound_texture_cube_map = ref;
     glBindTexture(GL_TEXTURE_CUBE_MAP, ref->service_id());
     ref = texture_manager()->GetDefaultTextureInfo(GL_TEXTURE_2D);
     state_.texture_units[tt].bound_texture_2d = ref;
     glBindTexture(GL_TEXTURE_2D, ref->service_id());
   }
   glActiveTexture(GL_TEXTURE0);
   CHECK_GL_ERROR();
 
-  ContextCreationAttribHelper attrib_parser;
-  if (!attrib_parser.Parse(attribs))
-    return false;
-
   if (offscreen) {
     if (attrib_parser.samples_ > 0 && attrib_parser.sample_buffers_ > 0 &&
         features().chromium_framebuffer_multisample) {
       // Per ext_framebuffer_multisample spec, need max bound on sample count.
       // max_sample_count must be initialized to a sane value.  If
       // glGetIntegerv() throws a GL error, it leaves its argument unchanged.
       GLint max_sample_count = 1;
       glGetIntegerv(GL_MAX_SAMPLES_EXT, &max_sample_count);
       offscreen_target_samples_ = std::min(attrib_parser.samples_,
                                            max_sample_count);
@@ skipping 8217 matching lines @@
   DoDidUseTexImageIfNeeded(texture, texture->target());
 }
 
 // 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 "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu