Okay, the shortcut for this action is simply missing. It’s the same than the existing Pick Shortest Path hotkey, but with Fill Region ticked and with shift key. To add it manually is semi difficult. But not too hard 
– Open User Preferences.
– Click at Input tab.
– Open the 3D View category
– Open the Mesh category
– Scroll down to the end of the mesh category, and click at Add New.
Expand this new created shortcut. We need to fill it with the right content now.
1) paste the following term into this edit box: mesh.shortest_path_pick
2) change this dropdown box to Mouse
3) change this dropdown box to Select
4) tick Shift and Ctrl
5) tick Fill Region
Don’t forget to save the user settings. And then you should have the needed functionality back