#6773 Regression Test : Add more input validation due to missing files

Running regression tests without valid external files revealed several crashes. Add guarding and remove asserts to make sure regression tests can be executed without crash.

ApplicationCode/ProjectDataModel/RimIntersection.cpp

@@ -210,9 +210,10 @@ cvf::ref<RivIntersectionHexGridInterface> RimIntersection::createHexGridInterfac
 
     RimEclipseView* eclipseView;
     this->firstAncestorOrThisOfType( eclipseView );
-    if ( eclipseView )
+    if ( eclipseView && eclipseView->mainGrid() )
     {
         RigMainGrid* grid = eclipseView->mainGrid();
+
         return new RivEclipseIntersectionGrid( grid, eclipseView->currentActiveCellInfo(), this->isInactiveCellsVisible() );
     }