Roll third_party/polymer.

third_party/polymer/v1_0/components-chromium/iron-selector/iron-multi-selectable-extracted.js

Index: third_party/polymer/v1_0/components-chromium/iron-selector/iron-multi-selectable-extracted.js
diff --git a/third_party/polymer/v1_0/components-chromium/iron-selector/iron-multi-selectable-extracted.js b/third_party/polymer/v1_0/components-chromium/iron-selector/iron-multi-selectable-extracted.js
index 38b18a869f2887733b152d4bf346e0366b67cf21..66da86debbeaf8703d14d0a3f0eaa12848b1e631 100644
--- a/third_party/polymer/v1_0/components-chromium/iron-selector/iron-multi-selectable-extracted.js
+++ b/third_party/polymer/v1_0/components-chromium/iron-selector/iron-multi-selectable-extracted.js
@@ -32,7 +32,7 @@
     },
 
     observers: [
-      '_updateSelected(selectedValues)'
+      '_updateSelected(selectedValues.splices)'
     ],
 
     /**
@@ -68,7 +68,7 @@
         Polymer.IronSelectableBehavior._updateAttrForSelected.apply(this);
       } else if (this._shouldUpdateSelection) {
         this.selectedValues = this.selectedItems.map(function(selectedItem) {
-          return this._indexToValue(this.indexOf(selectedItem));        
+          return this._indexToValue(this.indexOf(selectedItem));
         }, this).filter(function(unfilteredValue) {
           return unfilteredValue != null;
         }, this);
@@ -92,6 +92,13 @@
         for (var i = 0; i < selectedItems.length; i++) {
           this._selection.setItemSelected(selectedItems[i], true);
         }
+        // Check for items, since this array is populated only when attached
+        if (this.fallbackSelection && this.items.length && !this._selection.get().length) {
+          var fallback = this._valueToItem(this.fallbackSelection);
+          if (fallback) {
+            this.selectedValues = [this.fallbackSelection];
+          }
+        }
       } else {
         this._selection.clear();
       }
@@ -115,7 +122,6 @@
       } else {
         this.splice('selectedValues',i,1);
       }
-      this._selection.setItemSelected(this._valueToItem(value), unselected);
     },
 
     _valuesToItems: function(values) {