Ignore UI scaling when internal display isn't active (in docked mode, for example)

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 852 matching lines @@
     return active_display_list_[0];
   DisplayLayout layout = layout_store_->GetRegisteredDisplayLayout(
       GetCurrentDisplayIdPair());
   return GetDisplayForId(layout.primary_id);
 }
 
 size_t DisplayManager::GetNumDisplays() const {
   return active_display_list_.size();
 }
 
+bool DisplayManager::IsActiveDisplayId(int64 display_id) const {
+  return std::find_if(active_display_list_.begin(), active_display_list_.end(),
+                      [display_id](const gfx::Display& display) {
+                        return display.id() == display_id;
+                      }) != active_display_list_.end();
+}
+
 bool DisplayManager::IsInMirrorMode() const {
   return mirroring_display_id_ != gfx::Display::kInvalidDisplayID;
 }
 
 void DisplayManager::SetUnifiedDesktopEnabled(bool enable) {
   unified_desktop_enabled_ = enable;
   // There is no need to update the displays in mirror mode. Doing
   // this in hardware mirroring mode can cause crash because display
   // info in hardware mirroring comes from DisplayConfigurator.
   if (!IsInMirrorMode())
@@ skipping 520 matching lines @@
       gfx::Rect(new_secondary_origin, secondary_bounds.size()));
   secondary_display->UpdateWorkAreaFromInsets(insets);
 }
 
 void DisplayManager::RunPendingTasksForTest() {
   if (!software_mirroring_display_list_.empty())
     base::RunLoop().RunUntilIdle();
 }
 
 }  // namespace ash