Now ExpectActualDeclarationChecker in IDE context
uses common module descriptors for relevant checks.
Compiler still uses own module instead (see comment in checker)
So #KT-21771 Fixed
Try to report most mismatch errors on the 'impl' declaration. Only
report a mismatch error on the 'header' declaration if no error would be
otherwise reported on any 'impl' declaration in the compilation unit.
Also render declaration kind in the message
#KT-18447 In Progress