ignore large twips values like MSO does (cp#1000043)

Change-Id: Ib304245b6ae64c15cfb6c999580f73e5e228c440

writerfilter/source/dmapper/ConversionHelper.cxx

@@ -36,8 +36,6 @@ namespace writerfilter {
 namespace dmapper{
 namespace ConversionHelper{
 
-#define TWIP_TO_MM100(TWIP)     ((TWIP) >= 0 ? (((TWIP)*127L+36L)/72L) : (((TWIP)*127L-36L)/72L))
-
 sal_Int32 MakeBorderLine( sal_Int32 nSprmValue, table::BorderLine2& rToFill )
 {
     //TODO: Lines are always solid
@@ -231,6 +229,11 @@ OUString ConvertMSFormatStringToSO(
 
 sal_Int32 convertTwipToMM100(sal_Int32 _t)
 {
+    // It appears that MSO handles large twip values specially, probably legacy 16bit handling,
+    // anything that's bigger than 32767 appears to be simply ignored.
+    if( _t >= 0x8000 )
+        return 0;
+#define TWIP_TO_MM100(TWIP)     ((TWIP) >= 0 ? (((TWIP)*127L+36L)/72L) : (((TWIP)*127L-36L)/72L))
     return TWIP_TO_MM100( _t );
 }