Revert "Revert "WaE: comparison of integers of different signs""

This reverts commit e60f6ac2.

The "width" field is "int" in freetype 2.4.8 and "unsigned int" in 2.5.5

Change-Id: I4f7cc2bcf715890a85b956a5bf59667f634f31b5

vcl/generic/glyphs/gcach_ftyp.cxx

@@ -1206,7 +1206,8 @@ bool ServerFont::GetGlyphBitmap8( sal_GlyphId aGlyphId, RawBitmap& rRawBitmap )
         unsigned int x;
         for( int y = rRawBitmap.mnHeight; --y >= 0 ; )
         {
-            for( x = 0; x < rBitmapFT.width; ++x )
+            // note width is "int" in freetype 2.4.8 and "unsigned int" in 2.5.5
+            for (x = 0; x < static_cast<unsigned int>(rBitmapFT.width); ++x)
                 *(pDest++) = *(pSrc++);
             for(; x < rRawBitmap.mnScanlineSize; ++x )
                 *(pDest++) = 0;
@@ -1218,7 +1219,8 @@ bool ServerFont::GetGlyphBitmap8( sal_GlyphId aGlyphId, RawBitmap& rRawBitmap )
         for( int y = rRawBitmap.mnHeight; --y >= 0 ; )
         {
             unsigned char nSrc = 0;
-            for( x = 0; x < rBitmapFT.width; ++x, nSrc+=nSrc )
+            // note width is "int" in freetype 2.4.8 and "unsigned int" in 2.5.5
+            for (x = 0; x < static_cast<unsigned int>(rBitmapFT.width); ++x, nSrc+=nSrc)
             {
                 if( (x & 7) == 0 )
                     nSrc = *(pSrc++);