Roll Polymer to 1.3.1

third_party/polymer/v1_0/components-chromium/iron-autogrow-textarea/README.md

 
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-[![Build Status](https://travis-ci.org/PolymerElements/iron-autogrow-textarea.svg?branch=master)](https://travis-ci.org/PolymerElements/iron-autogrow-textarea)
+[![Build status](https://travis-ci.org/PolymerElements/iron-autogrow-textarea.svg?branch=master)](https://travis-ci.org/PolymerElements/iron-autogrow-textarea)
 
-_[Demo and API Docs](https://elements.polymer-project.org/elements/iron-autogrow-textarea)_
+_[Demo and API docs](https://elements.polymer-project.org/elements/iron-autogrow-textarea)_
 
 
 ##&lt;iron-autogrow-textarea&gt;
 
-
 `iron-autogrow-textarea` is an element containing a textarea that grows in height as more
 lines of input are entered. Unless an explicit height or the `maxRows` property is set, it will
 never scroll.
 
 Example:
 
-    <iron-autogrow-textarea></iron-autogrow-textarea>
+```html
+<iron-autogrow-textarea></iron-autogrow-textarea>
+```
 
 Because the `textarea`'s `value` property is not observable, you should use
 this element's `bind-value` instead for imperative updates.
 
 ### Styling
 
 The following custom properties and mixins are available for styling:
 
-Custom property | Description | Default
-----------------|-------------|----------
-`--iron-autogrow-textarea` | Mixin applied to the textarea | `{}`
+| Custom property | Description | Default |
+| --- | --- | --- |
+| `--iron-autogrow-textarea` | Mixin applied to the textarea | `{}` |
+| `--iron-autogrow-textarea-placeholder` | Mixin applied to the textarea placeholder | `{}` |