Currently it has "module mojo;", we should probably change it to "module ui.mojom;".

Firstly this is more consistent with other mojom files. Secondly, "module mojo" will generates mojo::blink:: namespace for the blink variant, and that is annoying. Because when you want to define a mojo::StructTraits specialization for some blink type Foo, you have to use ::blink::Foo (with :: at the beginning) to avoid looking up in the wrong namespace mojo::blink::