[Media Router WebUI] Use I18nBehavior to retrieve strings.
This change uses the I18nBehavior rather than calling loadTimeData.getString() for most of the strings when elements are initially created.
On Linux using a debug build, the UI load time is:
- before change: 3579.66ms (average 20 runs)
- after change: 3440.15ms (average 20 runs)
There is a 3.9% decrease in initial load time observed.
BUG=
549289
Committed:
https://crrev.com/26f90a390c9a8bab54c410c3ec60b52c7372b1eb
Cr-Commit-Position: refs/heads/master@{#387081}