Memoryleak caused by Maps; even post reconnect

Maps will be kept in memory even after disconnecting from a server.

Proof: https://youtu.be/2vcMEGn4IgI ( 1Min 32 Sec )
The Video shows multiple reconnects to a Server resulting in a OutOfMemoryError with Vanilla 1.8.6

The only possible workaround is to restart the Minecraft-Client.

This is related to MC-46345 ( MC-80297 ) and might be caused by the same faulty code - but the bug in itself is different.

Update
This issue is not fixed in 1.9.2.
Proof: https://www.youtube.com/watch?v=biQF9qu2ww8

MC-46345 only refers to the maps no longer updating.
This report refers to the memory never being cleared and ultimately causing a OutOfMemoryError.