Add a signal to tell the outside world when the crumb changed.

src/libtomahawk/widgets/breadcrumbbar.cpp

@@ -308,6 +308,7 @@ void BreadcrumbBar::currentChangedTriggered(QModelIndex const& index)
 {
     Q_ASSERT(m_selectionModel);
     m_selectionModel->setCurrentIndex( index, QItemSelectionModel::SelectCurrent);
+    emit currentIndexChanged(index);
 }
 
 void BreadcrumbBar::resizeEvent ( QResizeEvent * event )

src/libtomahawk/widgets/breadcrumbbar.h

@@ -131,6 +131,7 @@ public:
 
 signals:
     void rootClicked();
+    void currentIndexChanged(QModelIndex);
 
 protected:
     /**