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

Clipboard refactoring

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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/embedder_traits/lib.rs

@@ -132,6 +132,10 @@ pub enum EmbedderMsg {
     AllowUnload(IpcSender<bool>),
     /// Sends an unconsumed key event back to the embedder.
     Keyboard(KeyboardEvent),
+    /// Gets system clipboard contents
+    GetClipboardContents(IpcSender<String>),
+    /// Sets system clipboard contents
+    SetClipboardContents(String),
     /// Changes the cursor.
     SetCursor(Cursor),
     /// A favicon was detected
@@ -175,6 +179,8 @@ impl Debug for EmbedderMsg {
             EmbedderMsg::AllowUnload(..) => write!(f, "AllowUnload"),
             EmbedderMsg::AllowNavigationRequest(..) => write!(f, "AllowNavigationRequest"),
             EmbedderMsg::Keyboard(..) => write!(f, "Keyboard"),
+            EmbedderMsg::GetClipboardContents(..) => write!(f, "GetClipboardContents"),
+            EmbedderMsg::SetClipboardContents(..) => write!(f, "SetClipboardContents"),
             EmbedderMsg::SetCursor(..) => write!(f, "SetCursor"),
             EmbedderMsg::NewFavicon(..) => write!(f, "NewFavicon"),
             EmbedderMsg::HeadParsed => write!(f, "HeadParsed"),