Auto merge of #11735 - mrmiywj:reload-page-shortcut, r=jdm

add reload keyboard shortcut

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---
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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 #11686  (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [X] These changes do not require tests because this cannot be automated tested.

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5 files changed, 48 insertions, 0 deletions

diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index a987bd7bdd3..1c37c0df19c 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -1341,6 +1341,13 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                     self.start_shutting_down();
                 }
             }
+
+            WindowEvent::Reload => {
+                let msg = ConstellationMsg::Reload;
+                if let Err(e) = self.constellation_chan.send(msg) {
+                    warn!("Sending reload to constellation failed ({}).", e);
+                }
+            }
         }
     }
 
diff --git a/components/compositing/windowing.rs b/components/compositing/windowing.rs
index 72cb276121d..b67803b07c6 100644
--- a/components/compositing/windowing.rs
+++ b/components/compositing/windowing.rs
@@ -77,6 +77,8 @@ pub enum WindowEvent {
     Quit,
     /// Sent when a key input state changes
     KeyEvent(Key, KeyState, KeyModifiers),
+    /// Sent when Ctr+R/Apple+R is called to reload the current page.
+    Reload,
 }
 
 impl Debug for WindowEvent {
@@ -99,6 +101,7 @@ impl Debug for WindowEvent {
             WindowEvent::ResetZoom => write!(f, "ResetZoom"),
             WindowEvent::Navigation(..) => write!(f, "Navigation"),
             WindowEvent::Quit => write!(f, "Quit"),
+            WindowEvent::Reload => write!(f, "Reload"),
         }
     }
 }
diff --git a/components/constellation/constellation.rs b/components/constellation/constellation.rs
index 1197912a276..be73d3895d9 100644
--- a/components/constellation/constellation.rs
+++ b/components/constellation/constellation.rs
@@ -618,6 +618,10 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
                 debug!("constellation got webdriver command message");
                 self.handle_webdriver_msg(command);
             }
+            FromCompositorMsg::Reload => {
+                debug!("constellation got reload message");
+                self.handle_reload_msg();
+            }
         }
     }
 
@@ -1421,6 +1425,24 @@ impl<Message, LTF, STF> Constellation<Message, LTF, STF>
         }
     }
 
+    fn handle_reload_msg(&mut self) {
+        // Send Reload constellation msg to root script channel.
+        let root_pipeline_id = self.root_frame_id
+            .and_then(|root_frame_id| self.frames.get(&root_frame_id))
+            .map(|root_frame| root_frame.current);
+
+        if let Some(pipeline_id) = root_pipeline_id {
+            let msg = ConstellationControlMsg::Reload(pipeline_id);
+            let result = match self.pipelines.get(&pipeline_id) {
+                Some(pipeline) => pipeline.script_chan.send(msg),
+                None => return debug!("Pipeline {:?} got reload event after closure.", pipeline_id),
+            };
+            if let Err(e) = result {
+                self.handle_send_error(pipeline_id, e);
+            }
+        }
+    }
+
     fn handle_get_pipeline_title_msg(&mut self, pipeline_id: PipelineId) {
         let result = match self.pipelines.get(&pipeline_id) {
             None => return self.compositor_proxy.send(ToCompositorMsg::ChangePageTitle(pipeline_id, None)),
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index 8418071e908..e4b68c4952f 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -24,6 +24,8 @@ use devtools_traits::{ScriptToDevtoolsControlMsg, WorkerId};
 use document_loader::DocumentLoader;
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::DocumentBinding::{DocumentMethods, DocumentReadyState};
+use dom::bindings::codegen::Bindings::LocationBinding::LocationMethods;
+use dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
 use dom::bindings::conversions::{FromJSValConvertible, StringificationBehavior};
 use dom::bindings::global::GlobalRef;
 use dom::bindings::inheritance::Castable;
@@ -955,6 +957,8 @@ impl ScriptThread {
                 self.handle_framed_content_changed(containing_pipeline_id, subpage_id),
             ConstellationControlMsg::ReportCSSError(pipeline_id, filename, line, column, msg) =>
                 self.handle_css_error_reporting(pipeline_id, filename, line, column, msg),
+            ConstellationControlMsg::Reload(pipeline_id) =>
+                self.handle_reload(pipeline_id),
         }
     }
 
@@ -2106,6 +2110,14 @@ impl ScriptThread {
             sender.send(message).unwrap();
         }
     }
+
+    fn handle_reload(&self, pipeline_id: PipelineId) {
+        if let Some(context) = self.find_child_context(pipeline_id) {
+            let win = context.active_window();
+            let location = win.Location();
+            location.Reload();
+        }
+    }
 }
 
 impl Drop for ScriptThread {
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index cc8a06bf18e..5b1b169e8aa 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -193,6 +193,8 @@ pub enum ConstellationControlMsg {
     FramedContentChanged(PipelineId, SubpageId),
     /// Report an error from a CSS parser for the given pipeline
     ReportCSSError(PipelineId, String, usize, usize, String),
+    /// Reload the given page.
+    Reload(PipelineId),
 }
 
 /// Used to determine if a script has any pending asynchronous activity.
@@ -553,4 +555,6 @@ pub enum ConstellationMsg {
     TickAnimation(PipelineId, AnimationTickType),
     /// Dispatch a webdriver command
     WebDriverCommand(WebDriverCommandMsg),
+    /// Reload the current page.
+    Reload,
 }