Third patch to implement incognito support for Media Router.

This patch implements policies around incognito:

- OTR media routes created from OTR profiles are tracked. When the OTR
  profile is destroyed, we attempt to terminate the OTR media routes.

- Enforces that the OTR status of routes returned from to
  CreateRoute(), JoinRoute(), or ConnectRouteByRouteId() matches the OTR
  status of the profile that called them.

Patches will be submitted in this order:

1682853007: Adds support for off the record media routes.
This patch: Implements incognito policies for Media Router.
1702533003: Enables UI for incognito profiles.

BUG=524795

Review URL: https://codereview.chromium.org/1745493003

Cr-Commit-Position: refs/heads/master@{#381996}

• chrome/browser/media/android/router/media_router_android.cc[diff]
• chrome/browser/media/android/router/media_router_android.h[diff]
• chrome/browser/media/router/media_router.h[diff]
• chrome/browser/media/router/media_router.mojom[diff]
• chrome/browser/media/router/media_router_base.cc[diff]
• chrome/browser/media/router/media_router_base.h[diff]
• chrome/browser/media/router/media_router_factory.cc[diff]
• chrome/browser/media/router/media_router_factory.h[diff]
• chrome/browser/media/router/media_router_mojo_impl.cc[diff]
• chrome/browser/media/router/media_router_mojo_impl.h[diff]
• chrome/browser/media/router/media_router_mojo_impl_unittest.cc[diff]
• chrome/browser/media/router/mock_media_router.h[diff]
• chrome/browser/media/router/route_request_result.h[diff]
• chrome/browser/media/router/test_helper.h[diff]
• chrome/browser/ui/webui/media_router/media_router_ui.cc[diff]
• extensions/renderer/resources/media_router_bindings.js[diff]