MD Settings: Display: Add unified desktop control and modify api

extensions/common/api/system_display.idl

Index: extensions/common/api/system_display.idl
diff --git a/extensions/common/api/system_display.idl b/extensions/common/api/system_display.idl
index 6a1a921e8530bba82b5c29e53a09d180d3fd2470..d3a7e5386624de78faa9041a4a73f4ff1606a199 100644
--- a/extensions/common/api/system_display.idl
+++ b/extensions/common/api/system_display.idl
@@ -129,6 +129,10 @@ namespace system.display {
     // True if this display is enabled.
     boolean isEnabled;
 
+    // True for all displays when in unified desktop mode. See documentation
+    // for $(ref:enableUnifiedDesktop).
+    boolean isUnified;
+
     // The number of pixels per inch along the x-axis.
     double dpiX;
 
@@ -163,6 +167,12 @@ namespace system.display {
   };
 
   dictionary DisplayProperties {
+    // Chrome OS only. If set to true, changes the display mode to unifed
+    // desktop (see $(ref:enableUnifiedDesktop) for details). This is only valid
+    // for the primary display. If set, mirroringSourceId must not be set and
+    // other properties may not apply.

[Devlin, 2017/04/11 18:54:08]

Comment what the default is.

[stevenjb, 2017/04/11 19:34:47]

Done.

+    boolean? isUnified;
+
     // 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
@@ -203,6 +213,13 @@ namespace system.display {
     DisplayMode? displayMode;
   };
 
+  dictionary GetInfoFlags {
+    // If set to true, only a single $(ref:DisplayUnitInfo) will be returned
+    // by $(ref:getInfo) when in unified desktop mode (see
+    // $(ref:enableUnifiedDesktop)).

[Devlin, 2017/04/11 18:54:08]

Comment also what the default is.

[stevenjb, 2017/04/11 19:34:47]

Done.

+    boolean? singleUnified;

[Devlin, 2017/04/11 18:54:08]

singleUnified seems redundant to me - maybe singleDisplay or unifiedDisplay?

[stevenjb, 2017/04/11 19:34:47]

single = one result, unified = when in unified desktop mode.
'singleDisplay' is incorrect because multiple displays will be returned if not
in unified desktop mode.
'unifiedDisplay' is also misleading because we may not be in unified desktop
mode.

I don't think there is a good clear property name here. This is a restricted API
that only devs familiar with the concepts should be using.

+  };
+
   callback DisplayInfoCallback = void (DisplayUnitInfo[] displayInfo);
   callback DisplayLayoutCallback = void (DisplayLayout[] layouts);
   callback SetDisplayUnitInfoCallback = void();
@@ -210,11 +227,15 @@ namespace system.display {
   callback NativeTouchCalibrationCallback = void(boolean success);
 
   interface Functions {
-    // Get the information of all attached display devices.
-    static void getInfo(DisplayInfoCallback callback);
+    // Requests the information for all attached display devices.
+    // |flags|: See $(ref:GetInfoFlags).

[Devlin, 2017/04/11 18:54:08]

similar to the others, |flags| will already have a type that indicates what it
is.  Instead, say something like "The options used to determine which
information to return".

[stevenjb, 2017/04/11 19:34:47]

Done.

+    // |callback|: This will be invoked with an array of $(ref:DisplayUnitInfo).

[Devlin, 2017/04/11 18:54:08]

same as 238 (sorry, wrote these backwards)

[stevenjb, 2017/04/11 19:34:47]

Done.

+    static void getInfo(optional GetInfoFlags flags,
+                        DisplayInfoCallback callback);
 
-    // Get the layout info for all displays.
+    // Requests the layout info for all displays.
     // NOTE: This is only available to Chrome OS Kiosk apps and Web UI.
+    // |callback|: This will be invoked with an array of $(ref:DisplayLayout).

[Devlin, 2017/04/11 18:54:08]

The docs already say this by virtue of what the callback looks like.  Just say
something like "the callback to invoke with the results."

[stevenjb, 2017/04/11 19:34:47]

Done.

     static void getDisplayLayout(DisplayLayoutCallback callback);
 
     // Updates the properties for the display specified by |id|, according to