[NTP] Tweak app drag and drop.

chrome/browser/resources/ntp/apps.css

 /* Apps */
 
 #apps-content {
   position: relative;
   max-width: 780px;  /* (124 + margin * 2) * 6 */
 }
 
 html.apps-promo-visible #apps-content {
   max-width: 650px; /* (124 + margin * 2) * 5 */
 }
@@ skipping 75 matching lines @@
   -webkit-transition-delay: .5s;
   opacity: .9;
 }
 
 .app.dragging > .app-settings {
   background-image: none;
 }
 
 .app.dragging {
   opacity: .7;
-  z-index: 2;
 }
 
 #apps-content[launcher-animations=true] .app {
-  -webkit-transition: top .2s, left .2s, right .2s;
+  -webkit-transition: top .2s, left .2s, right .2s, opacity .2s;
 }
 
 @-webkit-keyframes bounce {
   0% {
     -webkit-transform: scale(0, 0);
   }
 
   60% {
     -webkit-transform: scale(1.2, 1.2);
   }
@@ skipping 77 matching lines @@
 */
 .app.web-store-entry.loner {
   position: absolute;
   left: 100%;
   top: 0;
 }
 
 html[dir=rtl] .app.web-store-entry.loner {
   right: 100%;
 }