tdf#105103 assertion failure crash

New document, insert mode on, press space (when autocorrect while
typing is on)

Change-Id: I54bc9a5cd1f9d8ef877eeca81d7d85ccd90e354a
Reviewed-on: https://gerrit.libreoffice.org/33651Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: pranavk <pranavk@collabora.co.uk>

sw/source/core/edit/acorrect.cxx

@@ -164,7 +164,7 @@ bool SwAutoCorrDoc::ReplaceRange( sal_Int32 nPos, sal_Int32 nSourceLength, const
     // text attributes with dummy characters must not be replaced!
     bool bDoReplace = true;
     sal_Int32 const nLen = rText.getLength();
-    for ( sal_Int32 n = 0; n < nLen; ++n )
+    for ( sal_Int32 n = 0; n < nLen && n + nPos < pNd->GetText().getLength(); ++n )
     {
         sal_Unicode const Char = pNd->GetText()[n + nPos];
         if ( ( CH_TXTATR_BREAKWORD == Char || CH_TXTATR_INWORD == Char )