Make sure the hist fill color and frame fill color are different in case of option BAR or HBAR.
Add missing call to PostLoadCheck.
Expose symbols of the currently loading library to the JIT (ROOT-6015).

While dlopening a library, its symbols cannot be found by dlsym(RTLD_GLOBAL,...).
The JIT can thus not resolve symbols from the library during dictionary initialization.
Thus we need to explicitly include the library.
This is now done through the LazyFunctionCreation interface.