Update to legend right-click

- Right-click now performs widget item change before contextual menu is handled (no more lost right-clicks)
- Right-clicks within multiple selection preserve selection, but still switch item
- Right-clicks outside of current selection clears selection and switches to new item before contextual menu

src/app/legend/qgslegend.cpp

@@ -387,12 +387,33 @@ void QgsLegend::mousePressEvent( QMouseEvent * e )
   else if ( e->button() == Qt::RightButton )
   {
     QTreeWidgetItem* item = itemAt( e->pos() );
-    if ( !item || item == currentItem() )
+    if ( !item )
+    {
+      setCurrentItem( 0 );
+    }
+    else if ( item != currentItem() )
+    {
+      if ( selectedItems().contains( item ) )
+      {
+        setCurrentItem( item, currentColumn(), QItemSelectionModel::NoUpdate );
+      }
+      else
+      {
+        clearSelection();
+        setCurrentItem( item );
+      }
+    }
+    else
     {
-      if ( !item )
-        setCurrentItem( 0 );
-      handleRightClickEvent( item, e->globalPos() );
+      // item is the current layer, but maybe previous selection was none
+      if ( !item->isSelected() )
+      {
+        item->setSelected( true );
+      }
     }
+    handleRightClickEvent( item, e->globalPos() );
+    e->ignore();
+    return;
   }
   QTreeWidget::mousePressEvent( e );
 }                               // contentsMousePressEvent