This is a simple replacement, it allows removing some manual free'ing in
the callers.
gdb/ChangeLog:
* common/buffer.c (buffer_xml_printf): Adjust.
* common/xml-utils.c (xml_escape_text): Change return type to
std::string, update code accordingly.
* common/xml-utils.h (xml_escape_text): Change return type to
std::string.
* rs6000-aix-tdep.c (rs6000_aix_shared_library_to_xml): Adjust.
* windows-tdep.c (windows_xfer_shared_library): Adjust.
* unittests/xml-utils-selftests.c (test_xml_escape_text):
Adjust.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_qxfer_libraries_svr4): Adjust to change of
return type of xml_escape_text.
* server.c (emit_dll_description): Likewise.
The following patch modifies xml_escape_text, so I took the opportunity
to write a unit test for it.
gdb/ChangeLog:
* Makefile.in (SUBDIR_UNITTESTS_SRCS): Add new source file.
(SUBDIR_UNITTESTS_OBS): Add new object file.
* unittests/xml-utils-selftests.c: New file.
