A question about a recipe: Golden Onion Tart with Gruyère and Thyme

I have a question about step 2 on the recipe "Golden Onion Tart with Gruyère and Thyme" from TasteFood. It says:

"While the onions are cooling, roll out the dough to fit in the bottom and up the side of a 10 inch round tart tin. Sprinkle half of the cheese over the bottom of the tart. Spoon onions into the shell and spread evenly. Sprinkle 1 teaspoon thyme over the onions. Brush the crust with the egg wash. Sprinkle the tart and crust with the remaining cheese." Re: "brush the crust with egg..." Do you mean just the edges of the crust, or should the whole crust be brushed before you add the cheese...?