Crop to content

So I have created an image within the default layer size, however, the image is smaller than the layer.

Is there a quick way to crop the layer (or all layers) to the overall size of the image?

When I export as .png there is a lot of dead space around the image.  I can easily crop this using Preview (in Mac) but am I aadding in an extra step here?  

Looked for a menu option, but can't see anything ovious.  A search online seems to find various ways of doing this, converting layers etc to smartobjects and then a few extra steps, but that seems like a long way round for a simple task.

In Gimp, there is an option 'crop to content'.  I'm assuming Photoshop has this option, called something else?

thanks