Perform direct routing of mouse events when the pointer is locked.

content/browser/web_contents/web_contents_view_mac.mm

Index: content/browser/web_contents/web_contents_view_mac.mm
diff --git a/content/browser/web_contents/web_contents_view_mac.mm b/content/browser/web_contents/web_contents_view_mac.mm
index 1d01ac835dbe810121a24de1a4014f1bd4de4307..b2366393bad700944ddbf977d318b1b59455f8e7 100644
--- a/content/browser/web_contents/web_contents_view_mac.mm
+++ b/content/browser/web_contents/web_contents_view_mac.mm
@@ -80,6 +80,9 @@ STATIC_ASSERT_ENUM(NSDragOperationEvery, blink::WebDragOperationEvery);
 
 namespace {
 
+WebContentsViewMac::RenderWidgetHostViewCreateFunction
+    g_create_render_widget_host_view = nullptr;
+
 content::ScreenInfo GetNSViewScreenInfo(NSView* view) {
   display::Display display =
       display::Screen::GetScreen()->GetDisplayNearestWindow(view);
@@ -104,6 +107,13 @@ content::ScreenInfo GetNSViewScreenInfo(NSView* view) {
 namespace content {
 
 // static
+void WebContentsViewMac::InstallCreateHookForTests(
+    RenderWidgetHostViewCreateFunction create_render_widget_host_view) {
+  CHECK_EQ(nullptr, g_create_render_widget_host_view);
+  g_create_render_widget_host_view = create_render_widget_host_view;
+}
+
+// static
 void WebContentsView::GetDefaultScreenInfo(ScreenInfo* results) {
   *results = GetNSViewScreenInfo(nil);
 }
@@ -350,8 +360,11 @@ RenderWidgetHostViewBase* WebContentsViewMac::CreateViewForWidget(
         render_widget_host->GetView());
   }
 
-  RenderWidgetHostViewMac* view = new RenderWidgetHostViewMac(
-      render_widget_host, is_guest_view_hack);
+  RenderWidgetHostViewMac* view =
+      g_create_render_widget_host_view
+          ? g_create_render_widget_host_view(render_widget_host,
+                                             is_guest_view_hack)
+          : new RenderWidgetHostViewMac(render_widget_host, is_guest_view_hack);
   if (delegate()) {
     base::scoped_nsobject<NSObject<RenderWidgetHostViewMacDelegate> >
         rw_delegate(