Move file capturer/renderer tests from the AppRTCMobile tests directory to the WebRTC tests directory. These tests do not test AppRTCMobile but rather WebRTC functionality. Therefore, they belong in WebRTC tests directory. BUG=webrtc:6545 Review-Url: https://codereview.webrtc.org/2632233002 Cr-Commit-Position: refs/heads/master@{#16115}