Remove gfx::FrameTime for a single clock source

content/browser/renderer_host/render_widget_host_view_mac.mm

 // 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 "content/browser/renderer_host/render_widget_host_view_mac.h"
 
 #import <objc/runtime.h>
 #include <OpenGL/gl.h>
 #include <QuartzCore/QuartzCore.h>
 
@@ skipping 54 matching lines @@
 #include "ui/accelerated_widget_mac/io_surface_layer.h"
 #include "ui/accelerated_widget_mac/surface_handle_types.h"
 #include "ui/base/cocoa/animation_utils.h"
 #import "ui/base/cocoa/fullscreen_window_manager.h"
 #import "ui/base/cocoa/underlay_opengl_hosting_window.h"
 #include "ui/base/layout.h"
 #include "ui/compositor/compositor.h"
 #include "ui/compositor/layer.h"
 #include "ui/events/keycodes/keyboard_codes.h"
 #include "ui/gfx/display.h"
-#include "ui/gfx/frame_time.h"
 #include "ui/gfx/geometry/dip_util.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/gfx/geometry/size_conversions.h"
 #include "ui/gfx/scoped_ns_graphics_context_save_gstate_mac.h"
 #include "ui/gfx/screen.h"
 #include "ui/gl/gl_switches.h"
 
 using content::BrowserAccessibility;
 using content::BrowserAccessibilityManager;
@@ skipping 3221 matching lines @@
 
 // "-webkit-app-region: drag | no-drag" is implemented on Mac by excluding
 // regions that are not draggable. (See ControlRegionView in
 // native_app_window_cocoa.mm). This requires the render host view to be
 // draggable by default.
 - (BOOL)mouseDownCanMoveWindow {
   return YES;
 }
 
 @end