Merge GVariant variable arguments support and put it under tests.
Also, remove the hack of the test case directly '#include'ing .c files
from glib/. Instead, create a non-installed gvariant-internal.h that
the tests can include and make the symbols in it visible on the symbol
table of the shared library. These symbols (as they are present in no
installed header files) are not part of the API of GLib.
Increase test coverage in a few other areas.
Issue caught by Michael Meeks. This patch based on his.
GVariantTypeInfo was dropping the reference count on the TypeInfo
structure before removing it from the hash table. This means that
another thread could come along and grab the value from the hash table
in the meantime.
Solve this by holding the lock on the table before dropping the
reference.
Also: move the hash table initialisation inside of the lock to remove
the standard double-initialisation race plus a more insidious issue
caused by the fact that we free the hash table once it becomes empty.
1) always emit ending type FIXED for fixed sized items
The serialiser needs to know if it dealing with a fixed sized item
in case the serialised data is corrupt and the item has the wrong
size.
2) add a macro that will be used by test cases to check that all
memory has been freed.
