* Upgrade vendored version of WebRender
* Patch WebRender: upgrade version of gleam
* Restore hit testing implementation
* Fix WebRender warnings
* Adapt Servo to new WebRender
* Update results
* Add a workaround for #30313
This slightly expands text boundaries in order to take into account the
fact that layout isn't measuring glyph boundaries.
This is a step toward upgrading WebRender, which will be upgraded and
patched in the `third_party` directory. This change vendors the current
private branch of WebRender that we use and adds a `patches` directory
which tracks the changes on top of the upstream WebRender commit
described by third_party/webrender/patches/head.