bluetooth: Avoid including non-blink mojo bindings in blink code
Blink should only use the blink variant of mojo bindings. Unfortunately,
this means we can no longer use the same enum across content/renderer and
blink.
To get around this, the embedder interface (WebBluetooth) uses int32 instead of
the enums and we cast to enum where appropriate.
Also removes unnecessary dependencies on mojo bindings.
BUG=
610415
Committed:
https://crrev.com/4928ab440dfc16789b8ec0d9c52717b78a41abb8
Cr-Commit-Position: refs/heads/master@{#405531}