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/constellation/constellation.rs

@@ -107,7 +107,6 @@ use canvas::canvas_paint_thread::CanvasPaintThread;
 use canvas::webgl_thread::WebGLThreads;
 use canvas_traits::canvas::CanvasId;
 use canvas_traits::canvas::CanvasMsg;
-use clipboard::{ClipboardContext, ClipboardProvider};
 use compositing::compositor_thread::CompositorProxy;
 use compositing::compositor_thread::Msg as ToCompositorMsg;
 use compositing::SendableFrameTree;
@@ -361,9 +360,6 @@ pub struct Constellation<Message, LTF, STF> {
     /// The size of the top-level window.
     window_size: WindowSizeData,
 
-    /// Means of accessing the clipboard
-    clipboard_ctx: Option<ClipboardContext>,
-
     /// Bits of state used to interact with the webdriver implementation
     webdriver: WebDriverData,
 
@@ -734,13 +730,6 @@ where
                         device_pixel_ratio: TypedScale::new(device_pixels_per_px.unwrap_or(1.0)),
                     },
                     phantom: PhantomData,
-                    clipboard_ctx: match ClipboardContext::new() {
-                        Ok(c) => Some(c),
-                        Err(e) => {
-                            warn!("Error creating clipboard context ({})", e);
-                            None
-                        },
-                    },
                     webdriver: WebDriverData::new(),
                     scheduler_chan: TimerScheduler::start(),
                     document_states: HashMap::new(),
@@ -1524,30 +1513,6 @@ where
             FromScriptMsg::Focus => {
                 self.handle_focus_msg(source_pipeline_id);
             },
-            FromScriptMsg::GetClipboardContents(sender) => {
-                let contents = match self.clipboard_ctx {
-                    Some(ref mut ctx) => {
-                        match ctx.get_contents() {
-                            Ok(c) => c,
-                            Err(e) => {
-                                warn!("Error getting clipboard contents ({}), defaulting to empty string", e);
-                                "".to_owned()
-                            },
-                        }
-                    },
-                    None => "".to_owned(),
-                };
-                if let Err(e) = sender.send(contents) {
-                    warn!("Failed to send clipboard ({})", e);
-                }
-            },
-            FromScriptMsg::SetClipboardContents(s) => {
-                if let Some(ref mut ctx) = self.clipboard_ctx {
-                    if let Err(e) = ctx.set_contents(s) {
-                        warn!("Error setting clipboard contents ({})", e);
-                    }
-                }
-            },
             FromScriptMsg::VisibilityChangeComplete(is_visible) => {
                 self.handle_visibility_change_complete(source_pipeline_id, is_visible);
             },

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"),

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();
     }
 }

components/script_traits/script_msg.rs

@@ -121,8 +121,6 @@ pub enum ScriptMsg {
     CreateCanvasPaintThread(Size2D<u64>, IpcSender<(IpcSender<CanvasMsg>, CanvasId)>),
     /// Notifies the constellation that this frame has received focus.
     Focus,
-    /// Requests that the constellation retrieve the current contents of the clipboard
-    GetClipboardContents(IpcSender<String>),
     /// Get the top-level browsing context info for a given browsing context.
     GetTopForBrowsingContext(
         BrowsingContextId,
@@ -183,8 +181,6 @@ pub enum ScriptMsg {
         AuxiliaryBrowsingContextLoadInfo,
         IpcSender<LayoutControlMsg>,
     ),
-    /// Requests that the constellation set the contents of the clipboard
-    SetClipboardContents(String),
     /// Mark a new document as active
     ActivateDocument,
     /// Set the document state for a pipeline (used by screenshot / reftests)
@@ -224,7 +220,6 @@ impl fmt::Debug for ScriptMsg {
             ChangeRunningAnimationsState(..) => "ChangeRunningAnimationsState",
             CreateCanvasPaintThread(..) => "CreateCanvasPaintThread",
             Focus => "Focus",
-            GetClipboardContents(..) => "GetClipboardContents",
             GetBrowsingContextInfo(..) => "GetBrowsingContextInfo",
             GetTopForBrowsingContext(..) => "GetParentBrowsingContext",
             GetChildBrowsingContextId(..) => "GetChildBrowsingContextId",
@@ -242,7 +237,6 @@ impl fmt::Debug for ScriptMsg {
             ScriptLoadedURLInIFrame(..) => "ScriptLoadedURLInIFrame",
             ScriptNewIFrame(..) => "ScriptNewIFrame",
             ScriptNewAuxiliary(..) => "ScriptNewAuxiliary",
-            SetClipboardContents(..) => "SetClipboardContents",
             ActivateDocument => "ActivateDocument",
             SetDocumentState(..) => "SetDocumentState",
             SetFinalUrl(..) => "SetFinalUrl",