Tidy up/deprecate some FrameContainer getters.
Tidy up/deprecate some FrameContainer getters.

FrameContainer shouldn't be responsible for exposing a WindowManager,
and shouldn't keep an IconManager reference just to pass it on to
other classes.

Change-Id: Id672fec154a19c999b078b3980681937f62bfb41
Reviewed-on: http://gerrit.dmdirc.com/2840
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <79e2475f81a6317276bf7cbb3958b20d289b78df@dmdirc.com>

ShaneMcC/DMDirc-Client,greboid/DMDirc,csmith/DMDirc,ShaneMcC/DMDirc-Client,greboid/DMDirc,DMDirc/DMDirc,DMDirc/DMDirc,DMDirc/DMDirc,csmith/DMDirc,greboid/DMDirc,csmith/DMDirc,DMDirc/DMDirc,csmith/DMDirc,ShaneMcC/DMDirc-Client,ShaneMcC/DMDirc-Client,greboid/DMDirc