`EmbedderMsg` was previously paired with an implicit
`Option<WebViewId>`, even though almost all variants were either always
`Some` or always `None`, depending on whether there was a `WebView
involved.
This patch adds the `WebViewId` to as many `EmbedderMsg` variants as
possible, so we can call their associated `WebView` delegate methods
without needing to check and unwrap the `Option`. In many cases, this
required more changes to plumb through the `WebViewId`.
Notably, all `Request`s now explicitly need a `WebView` or not, in order
to ensure that it is passed when appropriate.
Signed-off-by: Delan Azabani <dazabani@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>
This is the start of the organization of types that are in their own
crates in order to break dependency cycles between other crates. The
idea here is that putting these packages into their own directory is the
first step toward cleaning them up. They have grown organically and it
is difficult to explain to new folks where to put new shared types. Many
of these crates contain more than traits or don't contain traits at all.
Notably, `script_traits` isn't touched because it is vendored from
Gecko. Eventually this will move to `third_party`.
