Auto merge of #22224 - pyfisch:composition-webdriver, r=nox

Forward WebDriver CompositionEvent

Dispatch composition events in JS.
Insert characters from composition events to text input.

CompositionEvents currently can only be
created by WebDriver and not by embedders.

<!-- Please describe your changes on the following line: -->

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

<!-- Also, please make sure that "Allow edits from maintainers" checkbox is checked, so that we can help you if you get stuck somewhere along the way.-->

<!-- Pull requests that do not address these steps are welcome, but they will require additional verification as part of the review process. -->

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/22224)
<!-- Reviewable:end -->

1 files changed, 6 insertions, 0 deletions

diff --git a/components/script/textinput.rs b/components/script/textinput.rs
index 00272be528c..2f36b08dbd9 100644
--- a/components/script/textinput.rs
+++ b/components/script/textinput.rs
@@ -6,6 +6,7 @@
 
 use crate::clipboard_provider::ClipboardProvider;
 use crate::dom::bindings::str::DOMString;
+use crate::dom::compositionevent::CompositionEvent;
 use crate::dom::keyboardevent::KeyboardEvent;
 use keyboard_types::{Key, KeyState, Modifiers, ShortcutMatcher};
 use std::borrow::ToOwned;
@@ -831,6 +832,11 @@ impl<T: ClipboardProvider> TextInput<T> {
             .unwrap()
     }
 
+    pub fn handle_compositionend(&mut self, event: &CompositionEvent) -> KeyReaction {
+        self.insert_string(event.data());
+        KeyReaction::DispatchInput
+    }
+
     /// Whether the content is empty.
     pub fn is_empty(&self) -> bool {
         self.lines.len() <= 1 && self.lines.get(0).map_or(true, |line| line.is_empty())