GitLab

Re-submission with fixes of cl 1081234 (reverted by 1087371.)

  * Move the cast AccessibilityManager into
    chromecast/browser/accessibility.
  * Only compile and create AccessibilityManager if extensions
    enabled.

Bug: none
Test: manual
Change-Id: Id81fdb1711af84d8eecefd2061cca061826df39a
Reviewed-on: https://chromium-review.googlesource.com/1087650Reviewed-by: Alex Sakhartchouk <alexst@chromium.org>
Reviewed-by: Wez <wez@chromium.org>
Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Commit-Queue: Ryan Daum <rdaum@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565023}