fixes viewer CSS specificity and event listener removal

[brendankenny]

sorry, two last viewer flubs

1. This was an existing issue with the old viewer too: binding the message handler to this meant that a newly created function was being passed to addEventListener, so later attempts to remove the handler via a reference to the original, non-bound function was having no effect. Noticed when refreshing the viewer kept loading the same report as long as the triggering html report was still open in a tab.

2. save-as-gist is hidden by the CSS in the <template>s, which is after viewer.css in the page, so they win. This !importants it. Why does anyone let me write CSS

[paulirish]

save-as-gist is hidden by the CSS in the s, which is after viewer.css in the page, so they win.

should the templates be first in order? seems kinda more correct.

[brendankenny]

Yeah, that makes sense, though would the CSS have to be after not only the templates but where the templates end up inserted into the DOM, too?

[paulirish]

ah yes. this is correct. :) well then.. !important ftw.