update elements and fix some bugs

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

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@@ skipping 19 matching lines @@
 `--paper-input-container-invalid-color` | The foreground color of the error | `--google-red-500`
 `--paper-input-error`                   | Mixin applied to the error        | `{}`
 -->
 <dom-module id="paper-input-error">
   <template>
 
     <style>
       :host {
         display: inline-block;
         visibility: hidden;
-        float: left;
 
         color: var(--paper-input-container-invalid-color, --google-red-500);
 
         @apply(--paper-font-caption);
         @apply(--paper-input-error);
+        position: absolute;
       }
 
       :host([invalid]) {
         visibility: visible;
       };
     </style>
 
     <content></content>
-
+    
   </template>
 </dom-module>
 
 <script>
   Polymer({
     is: 'paper-input-error',
 
     behaviors: [
       Polymer.PaperInputAddonBehavior
     ],
 
     properties: {
       /**
        * True if the error is showing.
        */
       invalid: {
         readOnly: true,
         reflectToAttribute: true,
         type: Boolean
       }
     },
 
     update: function(state) {
       this._setInvalid(state.invalid);
     }
   });
 </script>