media: Add MediaPermission interface and MediaPermissionDispatcher.

MediaPermission is the interface for media code to check/request media related
permissions. MediaPermissionDispatcher is a MediaPermission implementation in
content/.

Plan of follow-up CL:
- Use MediaPermission in ProxyDecryptor and remove current protected media
  identifier info bar code in the browser process (on Android and ChromeOS).

BUG=446263
TEST=Tested on Android with encrypted-media-requestmediakeysystemaccess.html
layout test by calling MediaPermission methods manually in
webencryptedmediaclient_impl.cc.

Review URL: https://codereview.chromium.org/871663003

Cr-Commit-Position: refs/heads/master@{#313303}


CrOS-Libchrome-Original-Commit: 36b1f3badd1e3f36d0fb5eb63328d2de4da051ae
1 file changed
tree: 9a553cfd9df90ed29ca3867bc20d9c98ce863a64
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/