Update from https://crrev.com/311076

gpu/blink/webgraphicscontext3d_in_process_command_buffer_impl.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/blink/webgraphicscontext3d_in_process_command_buffer_impl.h"
+
+#include <GLES2/gl2.h>
+#ifndef GL_GLEXT_PROTOTYPES
+#define GL_GLEXT_PROTOTYPES 1
+#endif
+#include <GLES2/gl2ext.h>
+#include <GLES2/gl2extchromium.h>
+
+#include <string>
+
+#include "base/atomicops.h"
+#include "base/bind.h"
+#include "base/bind_helpers.h"
+#include "base/callback.h"
+#include "base/logging.h"
+#include "gpu/command_buffer/client/gles2_implementation.h"
+#include "gpu/command_buffer/common/gles2_cmd_utils.h"
+#include "gpu/skia_bindings/gl_bindings_skia_cmd_buffer.h"
+#include "ui/gfx/geometry/size.h"
+#include "ui/gl/gl_implementation.h"
+
+using gpu::gles2::GLES2Implementation;
+using gpu::GLInProcessContext;
+
+namespace gpu_blink {
+
+// static
+scoped_ptr<WebGraphicsContext3DInProcessCommandBufferImpl>
+WebGraphicsContext3DInProcessCommandBufferImpl::CreateViewContext(
+    const blink::WebGraphicsContext3D::Attributes& attributes,
+    bool lose_context_when_out_of_memory,
+    gfx::AcceleratedWidget window) {
+  DCHECK_NE(gfx::GetGLImplementation(), gfx::kGLImplementationNone);
+  bool is_offscreen = false;
+  return make_scoped_ptr(new WebGraphicsContext3DInProcessCommandBufferImpl(
+      scoped_ptr< ::gpu::GLInProcessContext>(),
+      attributes,
+      lose_context_when_out_of_memory,
+      is_offscreen,
+      window));
+}
+
+// static
+scoped_ptr<WebGraphicsContext3DInProcessCommandBufferImpl>
+WebGraphicsContext3DInProcessCommandBufferImpl::CreateOffscreenContext(
+    const blink::WebGraphicsContext3D::Attributes& attributes,
+    bool lose_context_when_out_of_memory) {
+  bool is_offscreen = true;
+  return make_scoped_ptr(new WebGraphicsContext3DInProcessCommandBufferImpl(
+      scoped_ptr< ::gpu::GLInProcessContext>(),
+      attributes,
+      lose_context_when_out_of_memory,
+      is_offscreen,
+      gfx::kNullAcceleratedWidget));
+}
+
+scoped_ptr<WebGraphicsContext3DInProcessCommandBufferImpl>
+WebGraphicsContext3DInProcessCommandBufferImpl::WrapContext(
+    scoped_ptr< ::gpu::GLInProcessContext> context,
+    const blink::WebGraphicsContext3D::Attributes& attributes) {
+  bool lose_context_when_out_of_memory = false;  // Not used.
+  bool is_offscreen = true;                      // Not used.
+  return make_scoped_ptr(new WebGraphicsContext3DInProcessCommandBufferImpl(
+      context.Pass(),
+      attributes,
+      lose_context_when_out_of_memory,
+      is_offscreen,
+      gfx::kNullAcceleratedWidget /* window. Not used. */));
+}
+
+WebGraphicsContext3DInProcessCommandBufferImpl::
+    WebGraphicsContext3DInProcessCommandBufferImpl(
+        scoped_ptr< ::gpu::GLInProcessContext> context,
+        const blink::WebGraphicsContext3D::Attributes& attributes,
+        bool lose_context_when_out_of_memory,
+        bool is_offscreen,
+        gfx::AcceleratedWidget window)
+    : share_resources_(attributes.shareResources),
+      webgl_context_(attributes.webGL),
+      is_offscreen_(is_offscreen),
+      window_(window),
+      context_(context.Pass()) {
+  ConvertAttributes(attributes, &attribs_);
+  attribs_.lose_context_when_out_of_memory = lose_context_when_out_of_memory;
+}
+
+WebGraphicsContext3DInProcessCommandBufferImpl::
+    ~WebGraphicsContext3DInProcessCommandBufferImpl() {
+}
+
+size_t WebGraphicsContext3DInProcessCommandBufferImpl::GetMappedMemoryLimit() {
+  return context_->GetMappedMemoryLimit();
+}
+
+bool WebGraphicsContext3DInProcessCommandBufferImpl::MaybeInitializeGL() {
+  if (initialized_)
+    return true;
+
+  if (initialize_failed_)
+    return false;
+
+  if (!context_) {
+    // TODO(kbr): More work will be needed in this implementation to
+    // properly support GPU switching. Like in the out-of-process
+    // command buffer implementation, all previously created contexts
+    // will need to be lost either when the first context requesting the
+    // discrete GPU is created, or the last one is destroyed.
+    gfx::GpuPreference gpu_preference = gfx::PreferDiscreteGpu;
+    context_.reset(GLInProcessContext::Create(
+        NULL, /* service */
+        NULL, /* surface */
+        is_offscreen_,
+        window_,
+        gfx::Size(1, 1),
+        NULL, /* share_context */
+        share_resources_,
+        attribs_,
+        gpu_preference,
+        ::gpu::GLInProcessContextSharedMemoryLimits(),
+        nullptr,
+        nullptr));
+  }
+
+  if (context_) {
+    base::Closure context_lost_callback = base::Bind(
+        &WebGraphicsContext3DInProcessCommandBufferImpl::OnContextLost,
+        base::Unretained(this));
+    context_->SetContextLostCallback(context_lost_callback);
+  } else {
+    initialize_failed_ = true;
+    return false;
+  }
+
+  real_gl_ = context_->GetImplementation();
+  setGLInterface(real_gl_);
+
+  if (real_gl_ && webgl_context_)
+    real_gl_->EnableFeatureCHROMIUM("webgl_enable_glsl_webgl_validation");
+
+  initialized_ = true;
+  return true;
+}
+
+bool
+WebGraphicsContext3DInProcessCommandBufferImpl::InitializeOnCurrentThread() {
+  if (!MaybeInitializeGL())
+    return false;
+  return context_ && !isContextLost();
+}
+
+bool WebGraphicsContext3DInProcessCommandBufferImpl::isContextLost() {
+  return context_lost_reason_ != GL_NO_ERROR;
+}
+
+WGC3Denum WebGraphicsContext3DInProcessCommandBufferImpl::
+    getGraphicsResetStatusARB() {
+  return context_lost_reason_;
+}
+
+::gpu::ContextSupport*
+WebGraphicsContext3DInProcessCommandBufferImpl::GetContextSupport() {
+  return real_gl_;
+}
+
+void WebGraphicsContext3DInProcessCommandBufferImpl::OnContextLost() {
+  // TODO(kbr): improve the precision here.
+  context_lost_reason_ = GL_UNKNOWN_CONTEXT_RESET_ARB;
+  if (context_lost_callback_) {
+    context_lost_callback_->onContextLost();
+  }
+}
+
+}  // namespace gpu_blink