Snapping: destroy index on dataChanged signal

Snapping caches on layers that have been changed by the provider or
by external sources are now invalidated.

(cherry-picked from e6fd2e2)

Author: Hugo Mercier

src/core/qgspointlocator.cpp

@@ -628,6 +628,7 @@ QgsPointLocator::QgsPointLocator( QgsVectorLayer* layer, const QgsCoordinateRefe
   connect( mLayer, SIGNAL( featureAdded( QgsFeatureId ) ), this, SLOT( onFeatureAdded( QgsFeatureId ) ) );
   connect( mLayer, SIGNAL( featureDeleted( QgsFeatureId ) ), this, SLOT( onFeatureDeleted( QgsFeatureId ) ) );
   connect( mLayer, SIGNAL( geometryChanged( QgsFeatureId, QgsGeometry& ) ), this, SLOT( onGeometryChanged( QgsFeatureId, QgsGeometry& ) ) );
+  connect( mLayer, SIGNAL( dataChanged() ), this, SLOT( destroyIndex() ) );
 }
 
 

src/core/qgspointlocator.h

@@ -207,8 +207,8 @@ class CORE_EXPORT QgsPointLocator : public QObject
 
   protected:
     bool rebuildIndex( int maxFeaturesToIndex = -1 );
+  protected slots:
     void destroyIndex();
-
   private slots:
     void onFeatureAdded( QgsFeatureId fid );
     void onFeatureDeleted( QgsFeatureId fid );