Fix plugin menu overlap.

For #346. Although this fixes the issue, it relies on edits to
`<core-list>`. I've submitted a pull request, and I'll keep the issue
open until I know it's resolved.

resources/report/bower.json

@@ -32,6 +32,6 @@
     "paper-progress": "Polymer/paper-progress#~0.5.0",
     "core-animated-pages": "Polymer/core-animated-pages#~0.5.1",
     "paper-toast": "Polymer/paper-toast#~0.5.1",
-    "core-list": "Polymer/core-list#~0.5.1"
+    "core-list": "WrinklyNinja/core-list#51e27f42c86a91cbbe0933f618b2e82905dda83a"
   }
 }

resources/report/css/overrides.css

@@ -74,6 +74,7 @@ html /deep/ paper-dropdown > div {
 /* This stops the main core-list having its own scrollbars. */
 #main > core-list {
     overflow-y: initial !important;
+    transform-style: preserve-3d;
 }
 
 /* This makes paper-menu-button icons align like paper-icon-buttons do. */

resources/report/html/loot-plugin-card.html

@@ -186,19 +186,6 @@ loot-clear-metadata
             this.shadowRoot.getElementById('clearMetadata').addEventListener('click', this.onClearMetadata, false);
 
             this.addEventListener('transitionend', this.onFlipEnd, false);
-
-            /* Because of the 3D flip effect used when accessing the editor,
-               plugin menus get hidden underneath later plugin cards unless
-               those cards have a lower z-index than the card the menu is part
-               of. Therefore, set this card's z-index to the negative of its
-               position in the plugin list.
-            */
-            var cards = this.parentElement.getElementsByTagName('loot-plugin-card');
-            for (var i = 0; i < cards.length; ++i) {
-                if (cards[i] == this) {
-                    this.style.zIndex = 10000 - i;
-                }
-            }
         },
 
         detached: function() {