[gui] keep dock icons one size smaller than toolbar icons

Author: nirvn

src/app/qgisappstylesheet.cpp

@@ -176,9 +176,21 @@ void QgisAppStyleSheet::buildStyleSheet( const QMap<QString, QVariant>& opts )
         .arg( palette.highlight().color().name() )
         .arg( palette.highlightedText().color().name() );
 
-  QString iconSize = opts.value( "iconSize" ).toString();
+  int iconSize = opts.value( "iconSize" ).toInt();
+  if ( iconSize > 32 )
+  {
+    iconSize -= 16;
+  }
+  else if ( iconSize == 32 ) 
+  {
+    iconSize = 24;
+  }
+  else
+  {
+    iconSize = 16;
+  }
+  
   QgsDebugMsg( QString( "iconSize: %1" ).arg( iconSize ) );
-  if ( iconSize.isEmpty() ) { return; }
   ss += QString( "QDockWidget QToolButton { icon-size: %1px; }" ).arg( iconSize );
 
   QgsDebugMsg( QString( "Stylesheet built: %1" ).arg( ss ) );