pidgin/pidgin

Fix a few issues with the CredentialProvider code that snuck past review

Testing Done:
Compiled and ran unit tests locally. Verified the warnings were gone from the unit test build and verified the warning was gone from the Purple-3.0.gir build.

Reviewed at https://reviews.imfreedom.org/r/168/
DOC_MODULE = 'facebook'
# Header files or dirs to ignore when scanning. Use base file/dir names
ignore_hfiles = [
]
# Extra options to supply to gtkdoc-scan.
scan_args = [
'--deprecated-guards=PURPLE_DISABLE_DEPRECATED',
'--rebuild-types',
'--rebuild-sections',
'--ignore-headers=' + ' '.join(ignore_hfiles),
]
# Extra SGML files that are included by $(DOC_MAIN_XML_FILE).
content_files = [
libpurple_version_xml,
]
gnome.gtkdoc(DOC_MODULE,
main_xml : DOC_MODULE + '-docs.xml',
src_dir : facebook_inc,
dependencies : facebook_dep,
install : true,
scan_args : scan_args,
gobject_typesfile : DOC_MODULE + '.types',
content_files : content_files)