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

Index: third_party/polymer/v1_0/components-chromium/iron-dropdown/README.md
diff --git a/third_party/polymer/v1_0/components-chromium/iron-dropdown/README.md b/third_party/polymer/v1_0/components-chromium/iron-dropdown/README.md
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@@ -1,4 +1,42 @@
-iron-dropdown
-=============
 
-An element that implements a simple drop-down menu widget with a trigger and content.
+<!---
+
+This README is automatically generated from the comments in these files:
+iron-dropdown.html
+
+Edit those files, and our readme bot will duplicate them over here!
+Edit this file, and the bot will squash your changes :)
+
+-->
+
+[![Build Status](https://travis-ci.org/PolymerElements/iron-dropdown.svg?branch=master)](https://travis-ci.org/PolymerElements/iron-dropdown)
+
+_[Demo and API Docs](https://elements.polymer-project.org/elements/iron-dropdown)_
+
+
+##&lt;iron-dropdown&gt;
+
+
+`<iron-dropdown>` is a generalized element that is useful when you have
+hidden content (`.dropdown-content`) that is revealed due to some change in
+state that should cause it to do so.
+
+Note that this is a low-level element intended to be used as part of other
+composite elements that cause dropdowns to be revealed.
+
+Examples of elements that might be implemented using an `iron-dropdown`
+include comboboxes, menubuttons, selects. The list goes on.
+
+The `<iron-dropdown>` element exposes attributes that allow the position
+of the `.dropdown-content` relative to the `.dropdown-trigger` to be
+configured.
+
+    <iron-dropdown horizontal-align="right" vertical-align="top">
+      <div class="dropdown-content">Hello!</div>
+    </iron-dropdown>
+
+In the above example, the `<div>` with class `.dropdown-content` will be
+hidden until the dropdown element has `opened` set to true, or when the `open`
+method is called on the element.
+
+