Switching AudioOutputAuthorizationHandler from using AudioManager interface to AudioSystem one.

BUG=672468
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2692203003
Cr-Commit-Position: refs/heads/master@{#450939}
void RenderProcessHostImpl::OnRegisterAecDumpConsumer(int id) {
  BrowserThread::PostTask(
      BrowserThread::UI, FROM_HERE,
      base::Bind(&RenderProcessHostImpl::RegisterAecDumpConsumerOnUIThread,
                 weak_factory_.GetWeakPtr(), id));
}

void RenderProcessHostImpl::OnRegisterAecDumpConsumer(int id) {
  BrowserThread::PostTask(
      BrowserThread::UI, FROM_HERE,
      base::Bind(&RenderProcessHostImpl::RegisterAecDumpConsumerOnUIThread,
                 weak_factory_.GetWeakPtr(), id));
}
