Resolves: fdo#76905 long delay when changing font size from % to pt

Change-Id: I33d72b51536ab96653ccda64c6e058c497289327

svtools/source/control/ctrlbox.cxx

@@ -1899,13 +1899,13 @@ void FontSizeBox::SetRelative( bool bNewRelative )
 
             if ( bPtRelative )
             {
+                Clear(); //clear early because SetDecimalDigits is a slow recalc
+
                 SetDecimalDigits( 1 );
                 SetMin( nPtRelMin );
                 SetMax( nPtRelMax );
                 SetUnit( FUNIT_POINT );
 
-                Clear();
-
                 short i = nPtRelMin, n = 0;
                 // JP 30.06.98: more than 100 values are not useful
                 while ( i <= nPtRelMax && n++ < 100 )
@@ -1916,12 +1916,13 @@ void FontSizeBox::SetRelative( bool bNewRelative )
             }
             else
             {
+                Clear(); //clear early because SetDecimalDigits is a slow recalc
+
                 SetDecimalDigits( 0 );
                 SetMin( nRelMin );
                 SetMax( nRelMax );
                 SetUnit( FUNIT_PERCENT );
 
-                Clear();
                 sal_uInt16 i = nRelMin;
                 while ( i <= nRelMax )
                 {
@@ -1932,6 +1933,8 @@ void FontSizeBox::SetRelative( bool bNewRelative )
         }
         else
         {
+            if (pFontList)
+                Clear(); //clear early because SetDecimalDigits is a slow recalc
             bRelative = bPtRelative = false;
             SetDecimalDigits( 1 );
             SetMin( 20 );