Make Interaction Media Features MQ dynamic on Windows.

content/browser/renderer_host/render_view_host_impl.cc

Index: content/browser/renderer_host/render_view_host_impl.cc
diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
index 27f9a45fc1c1a884b0473ebf7d8966ece433723b..1d6c9d6bc622f1c53c2968b9a48ebe91c71b3135 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -233,6 +233,8 @@ RenderViewHostImpl::RenderViewHostImpl(
 
   close_timeout_.reset(new TimeoutMonitor(base::Bind(
       &RenderViewHostImpl::ClosePageTimeout, weak_factory_.GetWeakPtr())));
+
+  input_device_change_observer_ = new InputDeviceChangeObserver(this);
 }
 
 RenderViewHostImpl::~RenderViewHostImpl() {
@@ -243,7 +245,7 @@ RenderViewHostImpl::~RenderViewHostImpl() {
                    base::Unretained(ResourceDispatcherHostImpl::Get()),
                    GetProcess()->GetID(), GetRoutingID()));
   }
-
+  delete input_device_change_observer_;
   delegate_->RenderViewDeleted(this);
   GetProcess()->RemoveObserver(this);
 }
@@ -905,6 +907,15 @@ void RenderViewHostImpl::OnWebkitPreferencesChanged() {
   updating_web_preferences_ = false;
 }
 
+bool RenderViewHostImpl::InputDeviceFeaturesChanged() {
+  WebPreferences prefs = GetWebkitPreferences();
+  int available_pointer_types, available_hover_types;
+  std::tie(available_pointer_types, available_hover_types) =
+      ui::GetAvailablePointerAndHoverTypes();
+  return prefs.available_pointer_types != available_pointer_types ||
+         prefs.available_hover_types != available_hover_types;
+}
+
 void RenderViewHostImpl::DisableScrollbarsForThreshold(const gfx::Size& size) {
   Send(new ViewMsg_DisableScrollbarsForSmallWindows(GetRoutingID(), size));
 }