Updated OSX to blacklist multisampling when multiple monitors are connected

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index 499f1616223036ecf528498a9d3b0b8a08391e9a..e29a7e620aeb6407b3884068ece3adb878fdeb00 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -400,7 +400,8 @@ RenderProcessHostImpl::RenderProcessHostImpl(
           dummy_shutdown_event_(false, false),
 #endif
           supports_browser_plugin_(supports_browser_plugin),
-          is_guest_(is_guest) {
+          is_guest_(is_guest),
+          gpu_observer_registered_(false) {
   widget_helper_ = new RenderWidgetHelper();
 
   ChildProcessSecurityPolicyImpl::GetInstance()->Add(GetID());
@@ -429,6 +430,11 @@ RenderProcessHostImpl::~RenderProcessHostImpl() {
   DCHECK(!run_renderer_in_process());
   ChildProcessSecurityPolicyImpl::GetInstance()->Remove(GetID());
 
+  if (gpu_observer_registered_) {
+    GpuDataManagerImpl::GetInstance()->RemoveObserver(this);
+    gpu_observer_registered_ = false;
+  }
+
   // We may have some unsent messages at this point, but that's OK.
   channel_.reset();
   while (!queued_messages_.empty()) {
@@ -552,6 +558,11 @@ bool RenderProcessHostImpl::Init() {
     fast_shutdown_started_ = false;
   }
 
+  if (!gpu_observer_registered_) {
+    gpu_observer_registered_ = true;
+    GpuDataManagerImpl::GetInstance()->AddObserver(this);
+  }
+
   is_initialized_ = true;
   return true;
 }
@@ -1773,4 +1784,20 @@ void RenderProcessHostImpl::OnCompositorSurfaceBuffersSwappedNoHost(
                                                  ack_params);
 }
 
+void RenderProcessHostImpl::OnGpuSwitching() {
+  for (RenderWidgetHostsIterator iter = GetRenderWidgetHostsIterator();
+       !iter.IsAtEnd();
+       iter.Advance()) {
+    const RenderWidgetHost* widget = iter.GetCurrentValue();
+    DCHECK(widget);
+    if (!widget || !widget->IsRenderView())
+      continue;
+
+    RenderViewHost* rvh =
+        RenderViewHost::From(const_cast<RenderWidgetHost*>(widget));
+
+    rvh->UpdateWebkitPreferences(rvh->GetWebkitPreferences());
+  }
+}
+
 }  // namespace content