DevTools: Inspect node styles (#33025)

* feat: retrieve applied styles

Signed-off-by: eri <eri@inventati.org>

* feat: preliminary style showing

Signed-off-by: eri <eri@inventati.org>

* chore: some style tests

Signed-off-by: eri <eri@inventati.org>

* feat: edit style rules

Signed-off-by: eri <eri@inventati.org>

* feat: css database

Signed-off-by: eri <eri@inventati.org>

* feat: computed styles

Signed-off-by: eri <eri@inventati.org>

* feat: inherited styles

Signed-off-by: eri <eri@inventati.org>

* feat: get stylesheet styles

Signed-off-by: eri <eri@inventati.org>

* feat: all styles in inspector

Signed-off-by: eri <eri@inventati.org>

* feat: multiple stylesheets

Signed-off-by: eri <eri@inventati.org>

* refactor: clean up

Signed-off-by: eri <eri@inventati.org>

* Some minor cleanup

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

---------

Signed-off-by: eri <eri@inventati.org>
Signed-off-by: Martin Robinson <mrobinson@igalia.com>
Co-authored-by: Martin Robinson <mrobinson@igalia.com>

components/devtools/actors/watcher.rs

@@ -59,7 +59,7 @@ impl SessionContext {
             // working propperly
             supported_resources: HashMap::from([
                 ("console-message", true),
-                ("css-change", false),
+                ("css-change", true),
                 ("css-message", false),
                 ("css-registered-properties", false),
                 ("document-event", false),