update elements and fix some bugs

test/fixtures/tooltip_button.html

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 <dom-module id="test-button">
     <template>
         <style>
             :host {
                 display: inline-block;
             }
 
             #button {
                 width: 100px;
                 height: 20px;
                 background-color: red;
             }
             paper-tooltip {
-                width: 70px;
+                width: 30px;
             }
 
         </style>
         <div id="button"></div>
-        <paper-tooltip id="tooltip" for="button">Tooltip text</paper-tooltip>
+        <paper-tooltip id="buttonTooltip" for="button">Tooltip text</paper-tooltip>
     </template>
 </dom-module>