Roll Polymer to 1.3.1

third_party/polymer/v1_0/components-chromium/iron-flex-layout/.bower.json

 {
   "name": "iron-flex-layout",
-  "version": "1.2.2",
+  "version": "1.3.0",
   "description": "Provide flexbox-based layouts",
   "keywords": [
     "web-components",
     "polymer",
     "layout"
   ],
   "main": "iron-flex-layout.html",
   "private": true,
   "license": "http://polymer.github.io/LICENSE.txt",
   "authors": [
     "The Polymer Authors"
   ],
   "repository": {
     "type": "git",
     "url": "git://github.com/PolymerElements/iron-flex-layout.git"
   },
   "dependencies": {
     "polymer": "Polymer/polymer#^1.1.0"
   },
   "devDependencies": {
-    "paper-styles": "polymerelements/paper-styles#^1.0.0",
-    "marked-element": "polymerelements/marked-element#^1.0.0",
-    "prism-element": "PolymerElements/prism-element#^1.0.0",
+    "iron-component-page": "polymerelements/iron-component-page#^1.0.0",
+    "iron-demo-helpers": "PolymerElements/iron-demo-helpers#^1.0.0",
+    "test-fixture": "PolymerElements/test-fixture#^1.0.0",
     "webcomponentsjs": "webcomponents/webcomponentsjs#^0.7.0",
-    "iron-component-page": "polymerelements/iron-component-page#^1.0.0"
+    "web-component-tester": "^4.0.0"
   },
   "ignore": [],
   "homepage": "https://github.com/PolymerElements/iron-flex-layout",
-  "_release": "1.2.2",
+  "_release": "1.3.0",
   "_resolution": {
     "type": "version",
-    "tag": "v1.2.2",
-    "commit": "41c4f35be1368afb770312b907a258175565dbdf"
+    "tag": "v1.3.0",
+    "commit": "434224c8cf63cb4bb1b66edb0dc58e4484f7c5b2"
   },
   "_source": "git://github.com/PolymerElements/iron-flex-layout.git",
   "_target": "^1.0.0",
   "_originalSource": "PolymerElements/iron-flex-layout"
 }