`paper-search-bar` NOT shown properly on IE and Edge

[firstor]

paper-search-bar is not shown properly on IE and Edge.
Please have a look at the attached screenshots for more information:

• Edge : additional x icon when the field gets focused
  

• IE : icons in the field (search, X) are v-aligned improperly and the search text is NOT displayed
  

Hope to fix this issue.

[firstor]

I tried to fix this issue myself: #27.