Add paper-menu-button and its dependencies to third_party/polymer

third_party/polymer/v1_0/components-chromium/paper-header-panel/bower.json

 {
   "name": "paper-header-panel",
-  "version": "1.0.2",
+  "version": "1.0.3",
   "description": "A header and content wrapper for layout with headers",
   "authors": [
     "The Polymer Authors"
   ],
   "keywords": [
     "web-components",
     "polymer",
     "layout"
   ],
+  "main": [
+    "paper-header-panel.html"
+  ],
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/PolymerElements/paper-header-panel.git"
+  },
   "private": true,
   "license": "http://polymer.github.io/LICENSE.txt",
   "homepage": "https://github.com/PolymerElements/paper-header-panel",
   "ignore": [],
   "dependencies": {
     "iron-flex-layout": "PolymerElements/iron-flex-layout#^1.0.0",
     "polymer": "Polymer/polymer#^1.0.0"
   },
   "devDependencies": {
     "web-component-tester": "*",
     "iron-component-page": "PolymerElements/iron-component-page#^1.0.0",
     "test-fixture": "PolymerElements/test-fixture#^1.0.0",
     "webcomponentsjs": "webcomponents/webcomponentsjs#^0.7.0",
     "paper-styles": "PolymerElements/paper-styles#^1.0.0"
   }
 }