Fix use condition_variable after delete

[Ratio2]

This fix crash on android. Crash reproduced in 4.1.2, 4.1.4 and 4.2.2. Crash logcat with:

scons platform=android target=template_debug dev_build=yes CCFLAGS=-fsanitize=hwaddress LINKFLAGS=-fsanitize=hwaddress

android-crash-3.txt