ohos: Add basic IME and keyboard support (#34188)

* ohos: Add basic IME and keyboard support

- Add extremely basic support for keyboard events
- Add basic IME support
   - Showing and hiding the IME
   - inserting text
   - deleting characters
   - very basic configuration of the IME

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* Apply suggestions from code review

Improve the log message

Co-authored-by: Josh Matthews <josh@joshmatthews.net>
Signed-off-by: Jonathan Schwender <55576758+jschwe@users.noreply.github.com>

* Update ports/servoshell/egl/ohos.rs

Co-authored-by: Mukilan Thiyagarajan <mukilanthiagarajan@gmail.com>
Signed-off-by: Jonathan Schwender <55576758+jschwe@users.noreply.github.com>

* ohos: Bump the minimum required SDK version to 5.0

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* ohos: Remove pub from callbacks

The callbacks don't need to be public, as we will be registering them.

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* Rename composition event

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* ohos: clippy in log

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* ohos: address some clippy warnings

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* ohos: Raise Error in mach if unsupported SDK version is used.

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

* Add keyboard-types dependency for android

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>

---------

Signed-off-by: Jonathan Schwender <jonathan.schwender@huawei.com>
Signed-off-by: Jonathan Schwender <55576758+jschwe@users.noreply.github.com>
Co-authored-by: Josh Matthews <josh@joshmatthews.net>
Co-authored-by: Mukilan Thiyagarajan <mukilanthiagarajan@gmail.com>

components/compositing/windowing.rs

@@ -10,7 +10,7 @@ use std::time::Duration;
 use base::id::{PipelineId, TopLevelBrowsingContextId};
 use embedder_traits::EventLoopWaker;
 use euclid::Scale;
-use keyboard_types::KeyboardEvent;
+use keyboard_types::{CompositionEvent, KeyboardEvent};
 use libc::c_void;
 use net::protocols::ProtocolRegistry;
 use script_traits::{
@@ -83,6 +83,8 @@ pub enum EmbedderEvent {
     ExitFullScreen(TopLevelBrowsingContextId),
     /// Sent when a key input state changes
     Keyboard(KeyboardEvent),
+    /// Sent for IME composition updates
+    IMEComposition(CompositionEvent),
     /// Sent when Ctr+R/Apple+R is called to reload the current page.
     Reload(TopLevelBrowsingContextId),
     /// Create a new top-level browsing context.
@@ -139,6 +141,7 @@ impl Debug for EmbedderEvent {
             EmbedderEvent::Refresh => write!(f, "Refresh"),
             EmbedderEvent::WindowResize => write!(f, "Resize"),
             EmbedderEvent::Keyboard(..) => write!(f, "Keyboard"),
+            EmbedderEvent::IMEComposition(..) => write!(f, "IMEComposition"),
             EmbedderEvent::AllowNavigationResponse(..) => write!(f, "AllowNavigationResponse"),
             EmbedderEvent::LoadUrl(..) => write!(f, "LoadUrl"),
             EmbedderEvent::MouseWindowEventClass(..) => write!(f, "Mouse"),

components/constellation/constellation.rs

@@ -125,7 +125,7 @@ use ipc_channel::ipc::{self, IpcReceiver, IpcSender};
 use ipc_channel::router::ROUTER;
 use ipc_channel::Error as IpcError;
 use keyboard_types::webdriver::Event as WebDriverInputEvent;
-use keyboard_types::KeyboardEvent;
+use keyboard_types::{CompositionEvent, KeyboardEvent};
 use log::{debug, error, info, trace, warn};
 use media::{GLPlayerThreads, WindowGLContext};
 use net_traits::pub_domains::reg_host;
@@ -1334,6 +1334,9 @@ where
             FromCompositorMsg::Keyboard(key_event) => {
                 self.handle_key_msg(key_event);
             },
+            FromCompositorMsg::IMECompositionEvent(ime_event) => {
+                self.handle_ime_msg(ime_event);
+            },
             FromCompositorMsg::IMEDismissed => {
                 self.handle_ime_dismissed();
             },
@@ -4235,6 +4238,42 @@ where
         }
     }
 
+    #[cfg_attr(
+        feature = "tracing",
+        tracing::instrument(skip_all, fields(servo_profiling = true))
+    )]
+    fn handle_ime_msg(&mut self, event: CompositionEvent) {
+        // Send to the focused browsing contexts' current pipeline.
+        let Some(focused_browsing_context_id) = self
+            .webviews
+            .focused_webview()
+            .map(|(_, webview)| webview.focused_browsing_context_id)
+        else {
+            warn!("No focused browsing context! Dropping IME event {event:?}");
+            return;
+        };
+        let event = CompositorEvent::CompositionEvent(event);
+        let pipeline_id = match self.browsing_contexts.get(&focused_browsing_context_id) {
+            Some(ctx) => ctx.pipeline_id,
+            None => {
+                return warn!(
+                    "{}: Got composition event for nonexistent browsing context",
+                    focused_browsing_context_id,
+                );
+            },
+        };
+        let msg = ConstellationControlMsg::SendEvent(pipeline_id, event);
+        let result = match self.pipelines.get(&pipeline_id) {
+            Some(pipeline) => pipeline.event_loop.send(msg),
+            None => {
+                return debug!("{}: Got composition event after closure", pipeline_id);
+            },
+        };
+        if let Err(e) = result {
+            self.handle_send_error(pipeline_id, e);
+        }
+    }
+
     #[cfg_attr(
         feature = "tracing",
         tracing::instrument(skip_all, fields(servo_profiling = true))

components/constellation/tracing.rs

@@ -66,6 +66,7 @@ mod from_compositor {
                 },
                 Self::IsReadyToSaveImage(..) => target!("IsReadyToSaveImage"),
                 Self::Keyboard(..) => target!("Keyboard"),
+                Self::IMECompositionEvent(..) => target!("IMECompositionEvent"),
                 Self::AllowNavigationResponse(..) => target!("AllowNavigationResponse"),
                 Self::LoadUrl(..) => target!("LoadUrl"),
                 Self::ClearCache => target!("ClearCache"),

components/servo/lib.rs

@@ -727,6 +727,16 @@ where
                 }
             },
 
+            EmbedderEvent::IMEComposition(ime_event) => {
+                let msg = ConstellationMsg::IMECompositionEvent(ime_event);
+                if let Err(e) = self.constellation_chan.send(msg) {
+                    warn!(
+                        "Sending composition event to constellation failed ({:?}).",
+                        e
+                    );
+                }
+            },
+
             EmbedderEvent::IMEDismissed => {
                 let msg = ConstellationMsg::IMEDismissed;
                 if let Err(e) = self.constellation_chan.send(msg) {

components/shared/compositing/constellation_msg.rs

@@ -10,7 +10,7 @@ use base::id::{BrowsingContextId, PipelineId, TopLevelBrowsingContextId, WebView
 use base::Epoch;
 use embedder_traits::Cursor;
 use ipc_channel::ipc::IpcSender;
-use keyboard_types::KeyboardEvent;
+use keyboard_types::{CompositionEvent, KeyboardEvent};
 use script_traits::{
     AnimationTickType, CompositorEvent, GamepadEvent, LogEntry, MediaSessionActionType,
     TraversalDirection, WebDriverCommandMsg, WindowSizeData, WindowSizeType,
@@ -34,6 +34,8 @@ pub enum ConstellationMsg {
     IsReadyToSaveImage(HashMap<PipelineId, Epoch>),
     /// Inform the constellation of a key event.
     Keyboard(KeyboardEvent),
+    /// Inform the constellation of a composition event (IME).
+    IMECompositionEvent(CompositionEvent),
     /// Whether to allow script to navigate.
     AllowNavigationResponse(PipelineId, bool),
     /// Request to load a page.
@@ -103,6 +105,7 @@ impl ConstellationMsg {
             GetFocusTopLevelBrowsingContext(..) => "GetFocusTopLevelBrowsingContext",
             IsReadyToSaveImage(..) => "IsReadyToSaveImage",
             Keyboard(..) => "Keyboard",
+            IMECompositionEvent(..) => "IMECompositionEvent",
             AllowNavigationResponse(..) => "AllowNavigationResponse",
             LoadUrl(..) => "LoadUrl",
             TraverseHistory(..) => "TraverseHistory",