Use DSF instead of UI scale if the native DSF is 1.25 and UI Scale is 0.8x (dsf=1.25 equivalent)

ash/display/display_manager.cc

 // 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 "ash/display/display_manager.h"
 
 #include <algorithm>
 #include <cmath>
 #include <set>
 #include <string>
@@ skipping 234 matching lines @@
   CommandLine* command_line = CommandLine::ForCurrentProcess();
   if (!command_line->HasSwitch(switches::kAshHostWindowBounds))
     return false;
   const string size_str =
       command_line->GetSwitchValueASCII(switches::kAshHostWindowBounds);
   vector<string> parts;
   base::SplitString(size_str, ',', &parts);
   for (vector<string>::const_iterator iter = parts.begin();
        iter != parts.end(); ++iter) {
     info_list.push_back(DisplayInfo::CreateFromSpec(*iter));
+    info_list.back().set_native(true);

[oshima, 2014/09/16 08:07:02]

these are to get "restore display settings" working on desktop. 

   }
   MaybeInitInternalDisplay(info_list[0].id());
   if (info_list.size() > 1 &&
       command_line->HasSwitch(switches::kAshEnableSoftwareMirroring)) {
     SetSecondDisplayMode(MIRRORING);
   }
   OnNativeDisplaysChanged(info_list);
   return true;
 }
 
 void DisplayManager::InitDefaultDisplay() {
   DisplayInfoList info_list;
   info_list.push_back(DisplayInfo::CreateFromSpec(std::string()));
+  info_list.back().set_native(true);
   MaybeInitInternalDisplay(info_list[0].id());
   OnNativeDisplaysChanged(info_list);
 }
 
 void DisplayManager::InitFontParams() {
 #if defined(OS_CHROMEOS)
   if (!HasInternalDisplay())
     return;
   const DisplayInfo& display_info =
       GetDisplayInfo(gfx::Display::InternalDisplayId());
@@ skipping 981 matching lines @@
       new_secondary_origin.Offset(-secondary_bounds.width(), offset);
       break;
   }
   gfx::Insets insets = secondary_display->GetWorkAreaInsets();
   secondary_display->set_bounds(
       gfx::Rect(new_secondary_origin, secondary_bounds.size()));
   secondary_display->UpdateWorkAreaFromInsets(insets);
 }
 
 }  // namespace ash