[1.7 BLOCKING LIVE] Host and guest crashes in Ultimate Pig Race multiplayer.

Verification Builds: 1117901

Summary: The game crashes for one of the players in Ultimate Pig Race (which is seeming random) both seemingly randomly and upon finishing a race. We experienced a crash when throwing the ornament, doing nothing but riding the pigs, and twice when one player crossed the finish line (once where the host crashed and once where the guest crashed). Just before the crash there is an assert:

Assertion failed: This should be empty by this point, if it's not we've got a problem!

Condition is false: mEntities.empty()

Function: MultiPlayerLevel::~MultiPlayerLevel in f:\darwinwork\18\s\handheld\src-client\common\client\multiplayer\multiplayerlevel.cpp @ 28

Impact: These crashes make Ultimate Pig Race multiplayer impossible to play, breaking an important selling point of the map.

Repro Steps:

1. Download and open Ultimate Pig Race, and have another player join.
2. Press the red button to start the factory race.
3. Both players should press a green button and mount the presented pig.
4. Play through the race, trying to complete three laps.

Observed Results: There are seemingly random crashes, and if the race is continued there is a crash when the first player crosses the finish line.

Expected Results: The game does not crash.

Screenshots / Videos Attached: No.

Regression Build: 1.6.0.8