Use the correct scale factor when rendering RemoteFrames with UseZoomForDSF.

content/renderer/render_frame_proxy.cc

 // Copyright 2014 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/renderer/render_frame_proxy.h"
 
 #include <stdint.h>
 #include <map>
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "content/child/web_url_request_util.h"
 #include "content/child/webmessageportchannel_impl.h"
 #include "content/common/content_security_policy_header.h"
+#include "content/common/content_switches_internal.h"
 #include "content/common/frame_messages.h"
 #include "content/common/frame_owner_properties.h"
 #include "content/common/frame_replication_state.h"
 #include "content/common/input_messages.h"
 #include "content/common/page_messages.h"
 #include "content/common/site_isolation_policy.h"
 #include "content/common/swapped_out_messages.h"
 #include "content/common/view_messages.h"
 #include "content/renderer/child_frame_compositing_helper.h"
 #include "content/renderer/render_frame_impl.h"
@@ skipping 405 matching lines @@
   if (source_frame) {
     RenderFrameImpl* source_render_frame =
         RenderFrameImpl::FromWebFrame(source_frame);
     if (source_render_frame)
       params.source_routing_id = source_render_frame->GetRoutingID();
   }
 
   Send(new FrameHostMsg_RouteMessageEvent(routing_id_, params));
 }
 
-void RenderFrameProxy::initializeChildFrame(
-    float scale_factor) {
+void RenderFrameProxy::initializeChildFrame() {
   Send(new FrameHostMsg_InitializeChildFrame(
-      routing_id_, scale_factor));
+      routing_id_, render_widget_->GetOriginalDeviceScaleFactor()));
 }
 
 void RenderFrameProxy::navigate(const blink::WebURLRequest& request,
                                 bool should_replace_current_entry) {
   FrameHostMsg_OpenURL_Params params;
   params.url = request.url();
   params.uses_post = request.httpMethod().utf8() == "POST";
   params.resource_request_body = GetRequestBodyForWebURLRequest(request);
   params.referrer = Referrer(
       blink::WebStringToGURL(
           request.httpHeaderField(blink::WebString::fromUTF8("Referer"))),
       request.referrerPolicy());
   params.disposition = CURRENT_TAB;
   params.should_replace_current_entry = should_replace_current_entry;
   params.user_gesture =
       blink::WebUserGestureIndicator::isProcessingUserGesture();
   blink::WebUserGestureIndicator::consumeUserGesture();
   Send(new FrameHostMsg_OpenURL(routing_id_, params));
 }
 
 void RenderFrameProxy::forwardInputEvent(const blink::WebInputEvent* event) {
   Send(new FrameHostMsg_ForwardInputEvent(routing_id_, event));
 }
 
 void RenderFrameProxy::frameRectsChanged(const blink::WebRect& frame_rect) {
-  Send(new FrameHostMsg_FrameRectChanged(routing_id_, frame_rect));
+  gfx::Rect rect = frame_rect;
+  if (IsUseZoomForDSFEnabled()) {
+    rect = gfx::ScaleToEnclosingRect(
+        rect, 1.f / render_widget_->GetOriginalDeviceScaleFactor());

[oshima, 2016/08/17 00:17:04]

We probably should update the RenderWIdget::convertViewportToWindow to use the
same and switch, but lgtm for now.

[lfg, 2016/08/17 15:37:51]

I'll put up another CL to update that.

+  }
+  Send(new FrameHostMsg_FrameRectChanged(routing_id_, rect));
 }
 
 void RenderFrameProxy::visibilityChanged(bool visible) {
   Send(new FrameHostMsg_VisibilityChanged(routing_id_, visible));
 }
 
 void RenderFrameProxy::didChangeOpener(blink::WebFrame* opener) {
   // A proxy shouldn't normally be disowning its opener.  It is possible to get
   // here when a proxy that is being detached clears its opener, in which case
   // there is no need to notify the browser process.
@@ skipping 13 matching lines @@
                                     blink::WebLocalFrame* source) {
   int source_routing_id = RenderFrameImpl::FromWebFrame(source)->GetRoutingID();
   Send(new FrameHostMsg_AdvanceFocus(routing_id_, type, source_routing_id));
 }
 
 void RenderFrameProxy::frameFocused() {
   Send(new FrameHostMsg_FrameFocused(routing_id_));
 }
 
 }  // namespace