Related: fdo#66524 don't invalidate font cache every time

The afm dirs are misdetected as having had something in it in the past and
having nothing in it now.

AFAICS it seems that this particular code has always been like this, so keeping
this fix separate for master only.

Change-Id: I8960d0b0d22ee24d5691eecdce262011dc141ea6

vcl/generic/fontmanager/fontmanager.cxx

@@ -1831,6 +1831,7 @@ void PrintFontManager::initialize()
                                 m_aFontFileToFontID[ aFileName ].insert( m_nNextFontID );
                                 m_aFonts[ m_nNextFontID++ ] = *it;
                                 m_pFontCache->updateFontCacheEntry( *it, false );
+                                ++nDirFonts;
 #if OSL_DEBUG_LEVEL > 2
                                 nBuiltinFonts++;
 #endif