Signed-off-by: Kingsley Yung <kingsley@kkoyung.dev>

Signed-off-by: Kingsley Yung <kingsley@kkoyung.dev>

)
We usually place `JSContext` as the first parameter of functions (after
`self`, if present).
The functions in `components/script/dom/servoparser/mod.rs` currently do
not follow this convention.
Move `cx: &mut JSContext` to the first parameter position in those
functions. Also, add a `use js::context::JSContext;` to the file so that
we don't need to use fully qualified path.
Testing: Refactoring. Existing tests are enough.
Fixes: Follow-up of
servo#44983 (comment)
Signed-off-by: Kingsley Yung <kingsley@kkoyung.dev>