Continuation of https://github.com/servo/servo/pull/42135, switch
Error::Type and Error::Range to also use CStrings internally, as they
are converted to CString for throwing JS exceptions (other get thrown as
DomException object, which uses rust string internally).
Changes in script crate are mechanical.
Testing: Should be covered by WPT tests.
Part of #42126
Signed-off-by: sagudev <16504129+sagudev@users.noreply.github.com>
Move testbinding interfaces to it's own module, to avoid cluttering dom
folder.
Testing: A successful build is enough
Part of #38901
---------
Signed-off-by: Gae24 <96017547+Gae24@users.noreply.github.com>