Bug 759398: Heap use-after-free in xmlDictComputeFastKey...

Bug 759398: Heap use-after-free in xmlDictComputeFastKey <https://bugzilla.gnome.org/show_bug.cgi?id=759398>

* parser.c:
(xmlParseNCNameComplex): Store start position instead of a
pointer to the name since the underlying buffer may change,
resulting in a stale pointer being used.
* result/errors/759398.xml: Added.
* result/errors/759398.xml.err: Added.
* result/errors/759398.xml.str: Added.
* test/errors/759398.xml: Added test case.