Resolves: fdo#73466 overflow on addition to COMPLETE_STRING

sw/source/core/text/itrcrsr.cxx:1632

SwTxtSizeInfo aSizeInf( GetInfo(), &rText, nCurrStart )

where nCurrStart is non 0 and the hidden 4th argument to SwTxtSizeInfo is
COMPLETE_STRING

in the past it was STRING_LEN unsigned 16bit 0xFFFF and so in GetMinLen in
sw/source/core/text/inftxt.cxx adding x to it resulted in x-1 which at least is
in bounds if selected by the std::min

Change-Id: I78f176804b79fb3c991677adb016579eabcfd56f
coverity#704294 Logically dead code

Change-Id: I347b8cfaf6d608e59dec25bb80a96ba862b3fcae
coverity#704298 Logically dead code

Change-Id: Ic2f52bb5ec072f11c99f20455e4536bc298b47c7
coverity#704300 Logically dead code

since af22075998a021d23ec1b266433f239d3200c35d "undoapi: attempt to fix broken
Undo contexts after executing a script" in 2010

Change-Id: I95f5ebf8960dc82d4a6da1ef186ba524e3cddfd1
coverity#704301 Logically dead code

Change-Id: I865979464a2abe51136b577fdb10ec0ae9faf11e