Move handling of Javascript console logs out of CRWWebController.

This CL moves the handling of Javascript console logs to an improved
architecture, but is a no-op in terms of functionality. This will allow
Javascript logs to be exposed in non-debug builds (instead of printing them to
the device console as is done currently).

Bug: 899851
Change-Id: I25eedc1f450df48acf66e4306f8846e0f761276f
Reviewed-on: https://chromium-review.googlesource.com/c/1338946
Commit-Queue: Mike Dougherty <michaeldo@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611547}
16 files changed