Remove two unnecessary params in ViewHostMsg_UpdateRect_Params

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 837 matching lines @@
       [cocoa_view_ setFrame:frame];
   } else {
     BaseView* superview = static_cast<BaseView*>([cocoa_view_ superview]);
     gfx::Rect rect2 = [superview flipNSRectToRect:[cocoa_view_ frame]];
     rect2.set_width(rect.width());
     rect2.set_height(rect.height());
     [cocoa_view_ setFrame:[superview flipRectToNSRect:rect2]];
   }
 }
 
+gfx::Vector2dF RenderWidgetHostViewMac::GetLastScrollOffset() const {
+  return last_scroll_offset_;
+}
+
 gfx::NativeView RenderWidgetHostViewMac::GetNativeView() const {
   return cocoa_view_;
 }
 
 gfx::NativeViewId RenderWidgetHostViewMac::GetNativeViewId() const {
   return reinterpret_cast<gfx::NativeViewId>(GetNativeView());
 }
 
 gfx::NativeViewAccessible RenderWidgetHostViewMac::GetNativeViewAccessible() {
   NOTIMPLEMENTED();
@@ skipping 506 matching lines @@
       const gfx::Size& desired_size) {
   if (browser_compositor_view_)
     return browser_compositor_view_->HasFrameOfSize(desired_size);
   return false;
 }
 
 void RenderWidgetHostViewMac::OnSwapCompositorFrame(
     uint32 output_surface_id, scoped_ptr<cc::CompositorFrame> frame) {
   TRACE_EVENT0("browser", "RenderWidgetHostViewMac::OnSwapCompositorFrame");
 
+  last_scroll_offset_ = frame->metadata.root_scroll_offset;
   if (frame->delegated_frame_data) {
     float scale_factor = frame->metadata.device_scale_factor;
 
     // Compute the frame size based on the root render pass rect size.
     cc::RenderPass* root_pass =
         frame->delegated_frame_data->render_pass_list.back();
     gfx::Size pixel_size = root_pass->output_rect.size();
     gfx::Size dip_size =
         ConvertSizeToDIP(scale_factor, pixel_size);
 
@@ skipping 1938 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