shell-app: Add "discrete_gpu" option when launching apps

And adapt existing callers to the new API. This will allow us to
implement a way to launch applications on the discrete GPU for systems
where an "Optimus" system exists.

https://bugzilla.gnome.org/show_bug.cgi?id=773117

js/misc/util.js

@@ -94,7 +94,7 @@ function spawnApp(argv) {
                                                       Gio.AppInfoCreateFlags.SUPPORTS_STARTUP_NOTIFICATION);
 
         let context = global.create_app_launch_context(0, -1);
-        app.launch([], context);
+        app.launch([], context, false);
     } catch(err) {
         _handleSpawnError(argv[0], err);
     }

js/ui/calendar.js

@@ -902,7 +902,7 @@ const EventsSection = new Lang.Class({
         let app = this._getCalendarApp();
         if (app.get_id() == 'evolution.desktop')
             app = Gio.DesktopAppInfo.new('evolution-calendar.desktop');
-        app.launch([], global.create_app_launch_context(0, -1));
+        app.launch([], global.create_app_launch_context(0, -1), false);
     },
 
     setDate: function(date) {

js/ui/components/autorunManager.js

@@ -64,7 +64,8 @@ function startAppForMount(app, mount) {
 
     try {
         retval = app.launch(files, 
-                            global.create_app_launch_context(0, -1))
+                            global.create_app_launch_context(0, -1),
+                            false)
     } catch (e) {
         log('Unable to launch the application ' + app.get_name()
             + ': ' + e.toString());

js/ui/remoteSearch.js

@@ -297,7 +297,7 @@ const RemoteSearchProvider = new Lang.Class({
         // the provider is not compatible with the new version of the interface, launch
         // the app itself but warn so we can catch the error in logs
         log('Search provider ' + this.appInfo.get_id() + ' does not implement LaunchSearch');
-        this.appInfo.launch([], global.create_app_launch_context(0, -1));
+        this.appInfo.launch([], global.create_app_launch_context(0, -1), false);
     }
 });
 

js/ui/status/network.js

@@ -1501,7 +1501,7 @@ const NMVPNSection = new Lang.Class({
         if (nItems > 1) {
             let appSys = Shell.AppSystem.get_default();
             let app = appSys.lookup_app('gnome-network-panel.desktop');
-            app.launch(0, -1);
+            app.launch(0, -1, false);
         } else {
             let connection = this._connections[0];
             Util.spawnApp(['gnome-control-center', 'network', 'show-device',