update elements and fix some bugs

lib/paper_input.dart

 // DO NOT EDIT: auto-generated with `pub run custom_element_apigen:update`
 
 /// Dart API for the polymer element `paper_input`.
 @HtmlImport('paper_input_nodart.html')
 library polymer_elements.lib.src.paper_input.paper_input;
 
 import 'dart:html';
 import 'dart:js' show JsArray, JsObject;
 import 'package:web_components/web_components.dart';
 import 'package:polymer_interop/polymer_interop.dart';
 import 'iron_form_element_behavior.dart';
 import 'paper_input_behavior.dart';
 import 'iron_control_state.dart';
 import 'iron_input.dart';
 import 'paper_input_container.dart';
 import 'paper_input_error.dart';
 import 'paper_input_char_counter.dart';
 
+/// 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.
 @CustomElementProxy('paper-input')
 class PaperInput extends HtmlElement with CustomElementProxyMixin, PolymerBase, IronFormElementBehavior, IronControlState, PaperInputBehavior, IronControlState {
   PaperInput.created() : super.created();
   factory PaperInput() => new Element.tag('paper-input');
 }