Get the default device scale factor from monitor

content/public/common/content_switches.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 "content/public/common/content_switches.h"
 
 namespace switches {
 
 // By default, file:// URIs cannot read other file:// URIs. This is an
 // override for developers who need the old behavior for testing.
@@ skipping 18 matching lines @@
 // Causes the browser process to crash on startup.
 const char kBrowserCrashTest[]              = "crash-test";
 
 // Path to the exe to run for the renderer and plugin subprocesses.
 const char kBrowserSubprocessPath[]         = "browser-subprocess-path";
 
 // Run Chrome in Chrome Frame mode. This means that Chrome expects to be run
 // as a dependent process of the Chrome Frame plugin.
 const char kChromeFrame[]                   = "chrome-frame";
 
-// The default device scale factor to apply to contents in the absence of
-// a viewport meta tag.
-const char kDefaultDeviceScaleFactor[]      = "default-device-scale-factor";
-
 // Disables client-visible 3D APIs, in particular WebGL and Pepper 3D.
 // This is controlled by policy and is kept separate from the other
 // enable/disable switches to avoid accidentally regressing the policy
 // support for controlling access to these APIs.
 const char kDisable3DAPIs[]                 = "disable-3d-apis";
 
 // Disable gpu-accelerated 2d canvas.
 const char kDisableAccelerated2dCanvas[]    = "disable-accelerated-2d-canvas";
 
 // Disables accelerated compositing.
@@ skipping 578 matching lines @@
 extern const char kFlingTapSuppressMaxDown[] = "fling-tap-suppress-max-down";
 
 // Maximum time between mousedown and mouseup to be considered a tap.
 extern const char kFlingTapSuppressMaxGap[] = "fling-tap-suppress-max-gap";
 
 // Forces usage of the test compositor. Needed to run ui tests on bots.
 extern const char kTestCompositor[]         = "test-compositor";
 #endif
 
 }  // namespace switches