Auto merge of #23564 - mmiecz:clipboard-refactoring, r=jdm

Clipboard refactoring

<!-- Please describe your changes on the following line: -->
This PR removes clipboard handling from the constellation. Instead, now embedder handles it.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #23440 (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because it is enough to test manually in input box, if copying and pasting still works .

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components/script/clipboard_provider.rs

@@ -2,9 +2,9 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
+use embedder_traits::EmbedderMsg;
 use ipc_channel::ipc::channel;
 use script_traits::{ScriptMsg, ScriptToConstellationChan};
-use std::borrow::ToOwned;
 
 pub trait ClipboardProvider {
     // blocking method to get the clipboard contents
@@ -16,31 +16,16 @@ pub trait ClipboardProvider {
 impl ClipboardProvider for ScriptToConstellationChan {
     fn clipboard_contents(&mut self) -> String {
         let (tx, rx) = channel().unwrap();
-        self.send(ScriptMsg::GetClipboardContents(tx)).unwrap();
+        self.send(ScriptMsg::ForwardToEmbedder(
+            EmbedderMsg::GetClipboardContents(tx),
+        ))
+        .unwrap();
         rx.recv().unwrap()
     }
     fn set_clipboard_contents(&mut self, s: String) {
-        self.send(ScriptMsg::SetClipboardContents(s)).unwrap();
-    }
-}
-
-pub struct DummyClipboardContext {
-    content: String,
-}
-
-impl DummyClipboardContext {
-    pub fn new(s: &str) -> DummyClipboardContext {
-        DummyClipboardContext {
-            content: s.to_owned(),
-        }
-    }
-}
-
-impl ClipboardProvider for DummyClipboardContext {
-    fn clipboard_contents(&mut self) -> String {
-        self.content.clone()
-    }
-    fn set_clipboard_contents(&mut self, s: String) {
-        self.content = s;
+        self.send(ScriptMsg::ForwardToEmbedder(
+            EmbedderMsg::SetClipboardContents(s),
+        ))
+        .unwrap();
     }
 }