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 150 matching lines @@
       num_connected_displays_(0),
       force_bounds_changed_(false),
       change_display_upon_host_resize_(false),
       second_display_mode_(EXTENDED),
       mirrored_display_id_(gfx::Display::kInvalidDisplayID),
       registered_internal_display_rotation_lock_(false),
       registered_internal_display_rotation_(gfx::Display::ROTATE_0) {
 #if defined(OS_CHROMEOS)
   change_display_upon_host_resize_ = !base::SysInfo::IsRunningOnChromeOS();
 #endif
-  DisplayInfo::SetAllowUpgradeToHighDPI(
-      ui::ResourceBundle::GetSharedInstance().GetMaxScaleFactor() ==
-      ui::SCALE_FACTOR_200P);
-

[oshima, 2014/09/16 17:11:42]

I also want to remove this, as installing 2x assets unintentionally enabled
this.

[Jun Mukai, 2014/09/16 18:18:56]

Removing this means allow_upgrade_to_high_dpi never gets true and may cause
problems on Pixel, right?

[oshima, 2014/09/16 18:47:15]

Pixel doesn't rely on this as its dfs is 2x.

   gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_ALTERNATE,
                                  screen_ash_.get());
   gfx::Screen* current_native =
       gfx::Screen::GetScreenByType(gfx::SCREEN_TYPE_NATIVE);
   // If there is no native, or the native was for shutdown,
   // use ash's screen.
   if (!current_native ||
       current_native == screen_for_shutdown) {
     gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE,
                                    screen_ash_.get());
@@ skipping 60 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);
   }
   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());
   gfx::SetFontRenderParamsDeviceScaleFactor(
-      display_info.device_scale_factor());
+      display_info.GetEffectiveDeviceScaleFactor());
 #endif  // OS_CHROMEOS
 }
 
 // static
 void DisplayManager::UpdateDisplayBoundsForLayoutById(
     const DisplayLayout& layout,
     const gfx::Display& primary_display,
     int64 secondary_display_id) {
   DCHECK_NE(gfx::Display::kInvalidDisplayID, secondary_display_id);
   UpdateDisplayBoundsForLayout(
@@ skipping 969 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