NTP4: Dragging app over trash should be more apparent.

chrome/browser/resources/ntp4/trash.js

Index: chrome/browser/resources/ntp4/trash.js
diff --git a/chrome/browser/resources/ntp4/trash.js b/chrome/browser/resources/ntp4/trash.js
index ae4180c0a1c4fed7b0ca845391bdf4b87c622a3c..9dc21a30f091d146c17e51b77ea7778c0e931c7a 100644
--- a/chrome/browser/resources/ntp4/trash.js
+++ b/chrome/browser/resources/ntp4/trash.js
@@ -43,6 +43,7 @@ cr.define('ntp4', function() {
     doDragOver: function(e) {
       ntp4.getCurrentlyDraggingTile().dragClone.classList.add(
           'hovering-on-trash');
+      this.classList.add('could-drop');
       ntp4.setCurrentDropEffect(e.dataTransfer, 'move');
       e.preventDefault();
     },
@@ -65,6 +66,7 @@ cr.define('ntp4', function() {
       var tile = ntp4.getCurrentlyDraggingTile();
       tile.firstChild.removeFromChrome();
       tile.landedOnTrash = true;
+      this.classList.remove('could-drop');
     },
 
     /**
@@ -74,6 +76,7 @@ cr.define('ntp4', function() {
     doDragLeave: function(e) {
       ntp4.getCurrentlyDraggingTile().dragClone.classList.remove(
           'hovering-on-trash');
+      this.classList.remove('could-drop');
     },
   };