Video end service sometimes not sent when using a secondary transport

[NicoleYarroch]

Bug Report

Due to TCP socket's resources getting reclaimed by the kernel when the app on the device is backgrounded, the TCP socket must be closed whenever the app on the device is backgrounded or the device is locked. But before the socket is closed an end video service control frame must be sent to close the current video stream.

This is done in the code currently in two separate classes, the SDLStreamingVideoLifecycleManager and the SDLSecondaryTransportManager, which are both registered for the UIApplicationWillResignActiveNotification. This creates a race condition where the transport might be destroyed by the SDLSecondaryTransportManager before the video end service control frame is sent by the SDLStreamingVideoLifecycleManager.

Reproduction Steps

1. Connect a navigation app to a head unit that supports secondary transports. Launch the SDL app if necessary.
2. Background the app on iPhone.

Expected Behavior

The end video service request should be sent and the TCP socket closed successfully.

Observed Behavior

The end video service request sometimes does not get sent and sometimes the TCP socket does not close successfully due to the thread not closing successfully when SDLTCPTransport disconnect is called.

OS & Version Information

• iOS Version: 13.0
• SDL iOS Version: 6.5
• Testing Against: SYNC 4

[NicoleYarroch]

Fixed in #1566