Language detection follow-up: moving language detection to only run after kLoadComplete event.

R=aboxhall,dmazzoni
BUG=889370

Change-Id: I423a97dccb1de48deaec862e66dfa3add7ec8341
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1519969
Commit-Queue: Chris Hall <chrishall@chromium.org>
Reviewed-by: Alice Boxhall <aboxhall@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#642387}
3 files changed