Some plugins were returning the number of specifications they have
added, while others were returning the total final number. Particularly
devious plugins (Minidump) were clearing the specification list
altogether. This resulted in nondeterministic failures (depending on
plugin ininitialization order) in TestSBModule.
This PR defines the problem away by having each plugin only return the
specifications it is responsible for. If the caller wants to merge them,
it is free to do so. This *might* be slighly less efficient, but this is
hardly hot code.
I'm not touching the ObjectFile::GetModuleSpecifications function (the
caller of all these functions) as the PR is big enough, although the
same approach might be warranted there as well.
Fixes https://github.com/llvm/llvm-project/issues/178625.
08c94c0ac3