[UseZoomForDSF] Guest view support

content/browser/renderer_host/render_widget_host_impl.cc

Index: content/browser/renderer_host/render_widget_host_impl.cc
diff --git a/content/browser/renderer_host/render_widget_host_impl.cc b/content/browser/renderer_host/render_widget_host_impl.cc
index 6516e5ec90383f4adb55923964b5f96c7cd21753..407cd5efe10d1b85558e2e2d79efb19fe94f15b0 100644
--- a/content/browser/renderer_host/render_widget_host_impl.cc
+++ b/content/browser/renderer_host/render_widget_host_impl.cc
@@ -211,6 +211,7 @@ RenderWidgetHostImpl::RenderWidgetHostImpl(RenderWidgetHostDelegate* delegate,
       next_browser_snapshot_id_(1),
       owned_by_render_frame_host_(false),
       is_focused_(false),
+      scale_input_to_viewport_(IsUseZoomForDSFEnabled()),
       hung_renderer_delay_(
           base::TimeDelta::FromMilliseconds(kHungRendererDelayMs)),
       new_content_rendering_delay_(
@@ -1264,7 +1265,7 @@ void RenderWidgetHostImpl::GetWebScreenInfo(blink::WebScreenInfo* result) {
   // TODO(sievers): find a way to make this done another way so the method
   // can be const.
   latency_tracker_.set_device_scale_factor(result->deviceScaleFactor);
-  if (IsUseZoomForDSFEnabled())
+  if (scale_input_to_viewport_)

[wjmaclean, 2016/01/20 19:41:54]

What is the advantage to storing this state? I guess it never changes during the
lifetime of the RWHI ...

[oshima, 2016/01/20 21:38:49]

It will change per RWHImpl instance. 

     input_router_->SetDeviceScaleFactor(result->deviceScaleFactor);
 }