use shadow dom when available

[MWalid]

tested with chrome, safari and firefox.

[MWalid]

This fix will work with browsers which support shadow dom natively like google chrome and others that don't like safari ....

[StatelessCat]

This fix will be helpful, do you plan to integrate it soon?
Thanks.

[benoitv-code]

Tested locally with Polymer 1.2.3 and page.js 1.6.4:

• Without this patch, page.js:
  • works well when shadow DOM is disabled.
  • doesn't work when shadow DOM is enabled.
• With this patch, page.js:
  • works well when shadow DOM is disabled.
  • works well when shadow DOM is enabled.

Any plan to integrate it soon?

Thanks!

[rstacruz]

thanks!