Add additional properties to display system info on ChromeOS

chrome/common/extensions/api/system_info_display.idl

 // Copyright (c) 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.
 
 namespace systemInfo.display {
 
   dictionary Bounds {
     // The x-coordinate of the upper-left corner.
     long left;
     // The y-coordinate of the upper-left corner.
     long top;
     // The width of the display in pixels.
     long width;
     // The height of the display in pixels.
     long height;
   };
 
   dictionary DisplayUnitInfo {
     // The unique identifier of the display.
     DOMString id;
     // The user-friendly name (e.g. "HP LCD monitor").
     DOMString name;
+    // Identifier of the display that is being mirrored on the display unit.
+    // If mirroring is not in progress, set to an empty string.

[asargent_no_longer_on_chrome, 2013/06/11 18:22:01]

You could also make the field optional (just add a question mark after the type
name), and then it would be undefined if mirroring is not in progress. I think
the code people would write would be the same either way, e.g.

chrome.systemInfo.display.getDisplayInfo(function(info) {
  if (info.mirroringSourceId) {
    // do something, etc.
    ...
  }
  ...
});

so feel free to leave it as you currently have if you want.

[tbarzic, 2013/06/11 23:56:53]

ok, I'll leave it as it is then

+    // Currently exposed only on ChromeOS. Will be set to an empty string on
+    // other platforms.
+    DOMString mirroringSourceId;
     // True if this is the primary display.
     boolean isPrimary;
     // True if this is an internal display.
     boolean isInternal;
     // True if this display is enabled.
     boolean isEnabled;
     // The number of pixels per inch along the x-axis.
     double dpiX;
     // The number of pixels per inch along the y-axis.
     double dpiY;
-    // The bounds of the display.
+    // The display's clockwise rotation in degrees relative to the vertical
+    // position.
+    // Currently exposed only on ChromeOS. Will be set to 0 on other platforms.
+    long rotation;
+    // The display's logical bounds. The logical coordinates are given relative
+    // to the primary display.
     Bounds bounds;
-    // The usable work area of the display.
+    // The display's bounds in the screen's coordinate system.
+    // Currently exposed only on ChromeOS. Will be set to empty bounds on
+    // other platforms.
+    Bounds visibleArea;
+    // 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;

[asargent_no_longer_on_chrome, 2013/06/11 18:22:01]

style nit: it would be a little easier to read these if you introduced a leading
newline above each starting comment block, e.g.

// Whatever
long foo;

// Something
DOMString bar;

[tbarzic, 2013/06/11 23:56:53]

Done.

   };
   
   callback DisplayInfoCallback = void (DisplayUnitInfo[] displayInfo);
 
   interface Functions {
     // Get the information of all attached display devices.
     static void getDisplayInfo(DisplayInfoCallback callback);
   };
   
   interface Events {
     // Fired when anything changes to the display configuration.
     static void onDisplayChanged();
   };
 };