[third_party] add polymer 1.2.3

polymer_1.2.3/bower_components/iron-fit-behavior/iron-fit-behavior.html

 <!--
 @license
 Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 Code distributed by Google as part of the polymer project is also
 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 -->
 
@@ skipping 73 matching lines @@
     get _fitHeight() {
       var fitHeight;
       if (this.fitInto === window) {
         fitHeight = this.fitInto.innerHeight;
       } else {
         fitHeight = this.fitInto.getBoundingClientRect().height;
       }
       return fitHeight;
     },
 
+    get _fitLeft() {
+      var fitLeft;
+      if (this.fitInto === window) {
+        fitLeft = 0;
+      } else {
+        fitLeft = this.fitInto.getBoundingClientRect().left;
+      }
+      return fitLeft;
+    },
+
+    get _fitTop() {
+      var fitTop;
+      if (this.fitInto === window) {
+        fitTop = 0;
+      } else {
+        fitTop = this.fitInto.getBoundingClientRect().top;
+      }
+      return fitTop;
+    },
+
     attached: function() {
       if (this.autoFitOnAttach) {
         if (window.getComputedStyle(this).display === 'none') {
           setTimeout(function() {
             this.fit();
           }.bind(this));
         } else {
           this.fit();
         }
       }
@@ skipping 76 matching lines @@
      */
     constrain: function() {
       var info = this._fitInfo;
       // position at (0px, 0px) if not already positioned, so we can measure the natural size.
       if (!this._fitInfo.positionedBy.vertically) {
         this.style.top = '0px';
       }
       if (!this._fitInfo.positionedBy.horizontally) {
         this.style.left = '0px';
       }
+      if (!this._fitInfo.positionedBy.vertically || !this._fitInfo.positionedBy.horizontally) {
+        // need position:fixed to properly size the element
+        this.style.position = 'fixed';
+      }
       // need border-box for margin/padding
       this.sizingTarget.style.boxSizing = 'border-box';
       // constrain the width and height if not already set
       var rect = this.getBoundingClientRect();
       if (!info.sizedBy.height) {
         this._sizeDimension(rect, info.positionedBy.vertically, 'top', 'bottom', 'Height');
       }
       if (!info.sizedBy.width) {
         this._sizeDimension(rect, info.positionedBy.horizontally, 'left', 'right', 'Width');
       }
@@ skipping 13 matching lines @@
     /**
      * Centers horizontally and vertically if not already positioned. This also sets
      * `position:fixed`.
      */
     center: function() {
       if (!this._fitInfo.positionedBy.vertically || !this._fitInfo.positionedBy.horizontally) {
         // need position:fixed to center
         this.style.position = 'fixed';
       }
       if (!this._fitInfo.positionedBy.vertically) {
-        var top = (this._fitHeight - this.offsetHeight) / 2;
+        var top = (this._fitHeight - this.offsetHeight) / 2 + this._fitTop;
         top -= this._fitInfo.margin.top;
         this.style.top = top + 'px';
       }
       if (!this._fitInfo.positionedBy.horizontally) {
-        var left = (this._fitWidth - this.offsetWidth) / 2;
+        var left = (this._fitWidth - this.offsetWidth) / 2 + this._fitLeft;
         left -= this._fitInfo.margin.left;
         this.style.left = left + 'px';
       }
     }
 
   };
 
 </script>