fix invalid memory access related to temporary object

e.g. export of ooo116460-2.xlsx

Change-Id: Id1ca2249e7b1f197a2df0d122c57dd97c4c4d785
don't use temporary object

This avoids invalid memory access with fdo45268-1.xlsx

Change-Id: If141df14d7d747023c944c83c2d8957abe8b95ad
workaround for DBG_UTIL XML correctness checks

The current check will always be hit as the StartXmlElement does not use
a call that puts the element on the stack. So copy the pattern for the
EndXmlElement class.

However we should work on getting rid of these ugly hacks.

Change-Id: Id1141f4afc78a0cae1e4b7accae76e6ae08b77a7
check for empty string before accessing first element

E.g. fdo#64530-1.xlsx

Change-Id: Iff2d026f6e876ab76c9b89b8200413d6c3a7a0e3
column storage might be changed, related lp#990868

Change-Id: Ibd196484c8c5199e7398726a250082c266a89229
avoid problems with poppler's and vcl's FontInfo during runtime

Change-Id: I1dbd256812cccae1e6ed0ad8bb34ce427e5e5be8

Conflicts:
	include/vcl/metric.hxx
	svtools/source/control/ctrlbox.cxx
	svtools/source/control/ctrltool.cxx
	svtools/source/control/stdmenu.cxx
	svx/source/sidebar/nbdtmg.cxx
make that variable protected again

Change-Id: I17235397e490458c250165c36bec97bf1ce326d7
fix new[]/delete mismatch

As seen by ooo90105-1.ods with memcheck

Change-Id: Ib976632aa52556132b3d05ebb33e8fb64d8d9890