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::CreateOffscreenCanvasCompositorFrameSinkProvider(
    blink::mojom::OffscreenCanvasCompositorFrameSinkProviderRequest request) {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);
  if (!offscreen_canvas_provider_) {
    offscreen_canvas_provider_.reset(
        new OffscreenCanvasCompositorFrameSinkProviderImpl());
  }
  offscreen_canvas_provider_->Add(std::move(request));
}

void RenderProcessHostImpl::CreateOffscreenCanvasCompositorFrameSinkProvider(
    blink::mojom::OffscreenCanvasCompositorFrameSinkProviderRequest request) {
  DCHECK_CURRENTLY_ON(BrowserThread::UI);
  if (!offscreen_canvas_provider_) {
    offscreen_canvas_provider_.reset(
        new OffscreenCanvasCompositorFrameSinkProviderImpl());
  }
  offscreen_canvas_provider_->Add(std::move(request));
}
