update elements and fix some bugs

lib/src/paper-input/paper-input.html

 <!--
 @license
 Copyright (c) 2015 The Polymer Project Authors. All rights reserved.
 This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
 The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
 The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
 Code distributed by Google as part of the polymer project is also
 subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
 -->
 <link rel="import" href="../polymer/polymer.html">
 <link rel="import" href="../iron-input/iron-input.html">
 <link rel="import" href="../iron-form-element-behavior/iron-form-element-behavior.html">
 <link rel="import" href="paper-input-behavior.html">
 <link rel="import" href="paper-input-container.html">
 <link rel="import" href="paper-input-error.html">
 <link rel="import" href="paper-input-char-counter.html">
 
 <!--
+Material design: [Text fields](https://www.google.com/design/spec/components/text-fields.html)
+
 `<paper-input>` is a single-line text field with Material Design styling.
 
     <paper-input label="Input label"></paper-input>
 
 It may include an optional error message or character counter.
 
     <paper-input error-message="Invalid input!" label="Input label"></paper-input>
     <paper-input char-counter label="Input label"></paper-input>
 
 It can also include custom prefix or suffix elements, which are displayed
 before or after the text input itself. In order for an element to be
 considered as a prefix, it must have the `prefix` attribute (and similarly
 for `suffix`).
 
     <paper-input label="total">
       <div prefix>$</div>
       <paper-icon-button suffix icon="clear"></paper-icon-button>
     </paper-input>
 
+A `paper-input` can use the native `type=search` or `type=file` features.
+However, since we can't control the native styling of the input, in these cases
+it's recommended to use a placeholder text, or `always-float-label`,
+as to not overlap the native UI (search icon, file button, etc.).
+
+    <paper-input label="search!" type="search"
+        placeholder="search for cats" autosave="test" results="5">
+    </paper-input>
+
 See `Polymer.PaperInputBehavior` for more API docs.
 
 ### Styling
 
 See `Polymer.PaperInputContainer` for a list of custom properties used to
 style this element.
 
 @group Paper Elements
 @element paper-input
 @hero hero.svg
@@ skipping 51 matching lines @@
         min$="[[min]]"
         max$="[[max]]"
         step$="[[step]]"
         name$="[[name]]"
         placeholder$="[[placeholder]]"
         readonly$="[[readonly]]"
         list$="[[list]]"
         size$="[[size]]"
         autocapitalize$="[[autocapitalize]]"
         autocorrect$="[[autocorrect]]"
-        on-change="_onChange">
+        on-change="_onChange"
+        autosave$="[[autosave]]"
+        results$="[[results]]"
+        accept$="[[accept]]"
+        multiple$="[[multiple]]">
 
       <content select="[suffix]"></content>
 
       <template is="dom-if" if="[[errorMessage]]">
         <paper-input-error>[[errorMessage]]</paper-input-error>
       </template>
 
       <template is="dom-if" if="[[charCounter]]">
         <paper-input-char-counter></paper-input-char-counter>
       </template>
 
     </paper-input-container>
 
   </template>
 </dom-module>
 
 <script>
   Polymer({
     is: 'paper-input',
 
     behaviors: [
       Polymer.IronFormElementBehavior,
       Polymer.PaperInputBehavior,
       Polymer.IronControlState
     ]
   });
 </script>