Add placeholder text to the Input component

sky/examples/stocks-fn/stocksapp.dart

 library stocksapp;
 
 import '../../framework/fn.dart';
 import '../../framework/components/drawer.dart';
 import '../../framework/components/drawer_header.dart';
 import '../../framework/components/fixed_height_scrollable.dart';
 import '../../framework/components/floating_action_button.dart';
 import '../../framework/components/icon.dart';
 import '../../framework/components/input.dart';
 import '../../framework/components/material.dart';
@@ skipping 68 matching lines @@
           children: [new Text('Settings')]
         ),
         new MenuItem(
           key: 'Help & Feedback',
           icon: 'action/help',
           children: [new Text('Help & Feedback')]
         )
       ]
     );
 
-    Node title = _isSearching ?
-        new Input(focused: true) : new Text('I am a stocks app');
+    Node title = _isSearching
+        ? new Input(focused: true, placeholder: 'Search stocks')
+        : new Text('I am a stocks app');
 
     var toolbar = new Toolbar(
       children: [
         new Icon(key: 'menu', style: _iconStyle,
             size: 24,
             type: 'navigation/menu_white')
           ..events.listen('click', _drawerAnimation.toggle),
         new Container(
           style: _titleStyle,
           children: [title]
@@ skipping 18 matching lines @@
           key: 'Content',
           style: _style,
           children: [toolbar, new Stocklist(stocks: _sortedStocks)]
         ),
         fab,
         drawer,
       ]
     );
   }
 }