Adds the touch calibration setting behind a chrome switch

extensions/common/api/system_display.idl

 // Copyright 2013 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.
 
 // Use the <code>system.display</code> API to query display metadata.
 namespace system.display {
 
   dictionary Bounds {
     // The x-coordinate of the upper-left corner.
     long left;
@@ skipping 139 matching lines @@
 
     // The usable work area of the display within the display bounds. The work
     // area excludes areas of the display reserved for OS, for example taskbar
     // and launcher.
     Bounds workArea;
 
     // The list of available display modes. The current mode will have
     // isSelected=true. Only available on Chrome OS. Will be set to an empty
     // array on other platforms.
     DisplayMode[] modes;
+
+    // True if this display has a touch input device associated with it.
+    boolean hasTouchSupport;
   };
 
   dictionary DisplayProperties {
     // Chrome OS only. If set and not empty, enables mirroring for this display.
     // Otherwise disables mirroring for this display. This value should indicate
     // the id of the source display to mirror, which must not be the same as the
     // id passed to setDisplayProperties. If set, no other property may be set.
     DOMString? mirroringSourceId;
 
     // If set to true, makes the display primary. No-op if set to false.
@@ skipping 124 matching lines @@
     // calibration data.
     // |id|: The display's unique identifier.
     static void touchCalibrationReset(DOMString id);
   };
 
   interface Events {
     // Fired when anything changes to the display configuration.
     static void onDisplayChanged();
   };
 };