Update from https://crrev.com/308331

ui/gl/gl_context.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 <string>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/threading/thread_local.h"
@@ skipping 34 matching lines @@
 }
 
 void GLContext::FlushEvent::Signal() {
   flag_.Set();
 }
 
 bool GLContext::FlushEvent::IsSignaled() {
   return flag_.IsSet();
 }
 
-GLContext::GLContext(GLShareGroup* share_group) : share_group_(share_group) {
+GLContext::GLContext(GLShareGroup* share_group) :
+    share_group_(share_group),
+    swap_interval_(1),
+    force_swap_interval_zero_(false) {
   if (!share_group_.get())
     share_group_ = new GLShareGroup;
 
   share_group_->AddContext(this);
 }
 
 GLContext::~GLContext() {
   share_group_->RemoveContext(this);
   if (GetCurrent() == this) {
     SetCurrent(NULL);
@@ skipping 105 matching lines @@
 }
 
 GLStateRestorer* GLContext::GetGLStateRestorer() {
   return state_restorer_.get();
 }
 
 void GLContext::SetGLStateRestorer(GLStateRestorer* state_restorer) {
   state_restorer_ = make_scoped_ptr(state_restorer);
 }
 
+void GLContext::SetSwapInterval(int interval) {
+  swap_interval_ = interval;
+  OnSetSwapInterval(force_swap_interval_zero_ ? 0 : swap_interval_);
+}
+
+void GLContext::ForceSwapIntervalZero(bool force) {
+  force_swap_interval_zero_ = force;
+  OnSetSwapInterval(force_swap_interval_zero_ ? 0 : swap_interval_);
+}
+
 bool GLContext::WasAllocatedUsingRobustnessExtension() {
   return false;
 }
 
 bool GLContext::InitializeDynamicBindings() {
   DCHECK(IsCurrent(NULL));
   static bool initialized = false;
   if (initialized)
     return initialized;
   initialized = InitializeDynamicGLBindings(GetGLImplementation(), this);
@@ skipping 36 matching lines @@
     : GLContext(share_group) {}
 
 GLContextReal::~GLContextReal() {}
 
 void GLContextReal::SetCurrent(GLSurface* surface) {
   GLContext::SetCurrent(surface);
   current_real_context_.Pointer()->Set(surface ? this : NULL);
 }
 
 }  // namespace gfx