Update bower.json for Polymer elements and add PRESUBMIT.py

third_party/polymer/v1_0/components-chromium/iron-meta/README.md

Index: third_party/polymer/v1_0/components-chromium/iron-meta/README.md
diff --git a/third_party/polymer/v1_0/components-chromium/iron-meta/README.md b/third_party/polymer/v1_0/components-chromium/iron-meta/README.md
index b3b0f273b6bc6ef92a60d31a9c3c5e2f524e36a5..26e2ddf72da23b6d69ef57537e962f11fa8fa9a4 100644
--- a/third_party/polymer/v1_0/components-chromium/iron-meta/README.md
+++ b/third_party/polymer/v1_0/components-chromium/iron-meta/README.md
@@ -16,23 +16,23 @@ Examples:
 If I create an instance like this:
 
 ```html
-<iron-meta key="info" keyUrl="foo/bar"></iron-meta>
+<iron-meta key="info" value="foo/bar"></iron-meta>
 ```
 
-Note that keyUrl="foo/bar" is the metadata I've defined. I could define more
+Note that value="foo/bar" is the metadata I've defined. I could define more
 attributes or use child nodes to define additional metadata.
 
 Now I can access that element (and it's metadata) from any iron-meta instance
 via the byKey method, e.g.
 
 ```javascript
-meta.byKey('info').getAttribute('keyUrl').
+meta.byKey('info').getAttribute('value');
 ```
 
 Pure imperative form would be like:
 
 ```javascript
-document.createElement('iron-meta').byKey('info').getAttribute('keyUrl');
+document.createElement('iron-meta').byKey('info').getAttribute('value');
 ```
 
 Or, in a Polymer element, you can include a meta in your template:
@@ -42,5 +42,5 @@ Or, in a Polymer element, you can include a meta in your template:
 ```
 
 ```javascript
-this.$.meta.byKey('info').getAttribute('keyUrl');
+this.$.meta.byKey('info').getAttribute('value');
 ```