Add flag to experiments to force high DPI mode.

ui/aura/monitor_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 "ui/aura/monitor_manager.h"
 
 #include <stdio.h>
 
+#include "base/command_line.h"
 #include "base/logging.h"
+#include "base/string_number_conversions.h"
+#include "content/public/common/content_switches.h"
 #include "ui/aura/env.h"
 #include "ui/aura/monitor_observer.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/root_window_host.h"
 #include "ui/gfx/monitor.h"
 #include "ui/gfx/rect.h"
 
 namespace aura {
 namespace {
 // Default bounds for a monitor.
@@ skipping 14 matching lines @@
   int x = 0, y = 0, width, height;
   float scale = 1.0f;
   if (sscanf(spec.c_str(), "%dx%d*%f", &width, &height, &scale) >= 2) {
     bounds.set_size(gfx::Size(width, height));
   } else if (sscanf(spec.c_str(), "%d+%d-%dx%d*%f", &x, &y, &width, &height,
                     &scale) >= 4 ) {
     bounds = gfx::Rect(x, y, width, height);
   } else if (use_fullscreen_host_window_) {
     bounds = gfx::Rect(aura::RootWindowHost::GetNativeScreenSize());
   }
+
+  // Setting a default device scale factor overrides the monitor scale factor.
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kDefaultDeviceScaleFactor)) {
+    int default_device_scale_factor;
+    base::StringToInt(CommandLine::ForCurrentProcess()->GetSwitchValueASCII(

[sky, 2012/04/27 19:44:46]

check return value.

[flackr, 2012/04/30 14:05:15]

Done.

+                          switches::kDefaultDeviceScaleFactor),
+                      &default_device_scale_factor);
+    scale = default_device_scale_factor;
+  }
+
   gfx::Monitor monitor(synthesized_monitor_id++, bounds);
   monitor.set_device_scale_factor(scale);
   DVLOG(1) << "Monitor bounds=" << bounds.ToString() << ", scale=" << scale;
   return monitor;
 }
 
 // static
 RootWindow* MonitorManager::CreateRootWindowForPrimaryMonitor() {
   MonitorManager* manager = aura::Env::GetInstance()->monitor_manager();
   RootWindow* root =
@@ skipping 26 matching lines @@
   FOR_EACH_OBSERVER(MonitorObserver, observers_,
                     OnMonitorAdded(monitor));
 }
 
 void MonitorManager::NotifyMonitorRemoved(const gfx::Monitor& monitor) {
   FOR_EACH_OBSERVER(MonitorObserver, observers_,
                     OnMonitorRemoved(monitor));
 }
 
 }  // namespace aura