Do not change origin of multifile class bridges to something else
because, as it turns out, there are numerous origin-specific checks in
the codegen that start to behave differently for multifile bridges.
Instead of the method-targeted origin MULTIFILE_BRIDGE, use new class
origin JVM_MULTIFILE_CLASS to detect whether a declaration is a
multifile bridge.
#KT-40198 Fixed
#KT-43145 Fixed
The change is a bit complicated because the name mapping logic is
refactored so that we would compute the needed suffix first (either
module name, or multifile part class name), and then shove it into the
mangled name between the original function name and "$default", if the
function in question is the default arguments adapter.
The main motivation for this change was to fix KT-41809, but as a side
effect, private functions with default arguments in multifile parts now
also contain the file name, just like normal private functions.
#KT-41809 Fixed
Alexander Udalov