Auto merge of #5559 - glennw:iframe-focus, r=jdm

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6 files changed, 141 insertions, 39 deletions

diff --git a/components/compositing/constellation.rs b/components/compositing/constellation.rs
index 3d098fbe01e..0520fa4859f 100644
--- a/components/compositing/constellation.rs
+++ b/components/compositing/constellation.rs
@@ -87,6 +87,9 @@ pub struct Constellation<LTF, STF> {
     /// The next free ID to assign to a frame.
     next_frame_id: FrameId,
 
+    /// Pipeline ID that has currently focused element for key events.
+    focus_pipeline_id: Option<PipelineId>,
+
     /// Navigation operations that are in progress.
     pending_frames: Vec<FrameChange>,
 
@@ -198,6 +201,7 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
                 next_pipeline_id: PipelineId(0),
                 root_frame_id: None,
                 next_frame_id: FrameId(0),
+                focus_pipeline_id: None,
                 time_profiler_chan: time_profiler_chan,
                 mem_profiler_chan: mem_profiler_chan,
                 window_size: WindowSizeData {
@@ -387,6 +391,10 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
                 debug!("constellation got get root pipeline message");
                 self.handle_get_root_pipeline(resp_chan);
             }
+            ConstellationMsg::FocusMsg(pipeline_id) => {
+                debug!("constellation got focus message");
+                self.handle_focus_msg(pipeline_id);
+            }
         }
         true
     }
@@ -594,6 +602,11 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
             self.pipeline_to_frame_map.get(&pipeline_id).map(|id| *id)
         }).unwrap();
 
+        // Check if the currently focused pipeline is the pipeline being replaced
+        // (or a child of it). This has to be done here, before the current
+        // frame tree is modified below.
+        let update_focus_pipeline = self.focused_pipeline_in_tree(frame_id);
+
         // Get the ids for the previous and next pipelines.
         let (prev_pipeline_id, next_pipeline_id) = {
             let frame = self.mut_frame(frame_id);
@@ -621,6 +634,13 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
             (prev, next)
         };
 
+        // If the currently focused pipeline is the one being changed (or a child
+        // of the pipeline being changed) then update the focus pipeline to be
+        // the replacement.
+        if update_focus_pipeline {
+            self.focus_pipeline_id = Some(next_pipeline_id);
+        }
+
         // Suspend the old pipeline, and resume the new one.
         self.pipeline(prev_pipeline_id).freeze();
         self.pipeline(next_pipeline_id).thaw();
@@ -645,10 +665,16 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
     }
 
     fn handle_key_msg(&self, key: Key, state: KeyState, mods: KeyModifiers) {
-        match self.root_frame_id {
-            Some(root_frame_id) => {
-                let root_frame = self.frame(root_frame_id);
-                let pipeline = self.pipeline(root_frame.current);
+        // Send to the explicitly focused pipeline (if it exists), or the root
+        // frame's current pipeline. If neither exist, fall back to sending to
+        // the compositor below.
+        let target_pipeline_id = self.focus_pipeline_id.or(self.root_frame_id.map(|frame_id| {
+            self.frame(frame_id).current
+        }));
+
+        match target_pipeline_id {
+            Some(target_pipeline_id) => {
+                let pipeline = self.pipeline(target_pipeline_id);
                 let ScriptControlChan(ref chan) = pipeline.script_chan;
                 let event = CompositorEvent::KeyEvent(key, state, mods);
                 chan.send(ConstellationControlMsg::SendEvent(pipeline.id,
@@ -691,7 +717,39 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
         resp_chan.send(pipeline_id).unwrap();
     }
 
+    fn focus_parent_pipeline(&self, pipeline_id: PipelineId) {
+        // Send a message to the parent of the provided pipeline (if it exists)
+        // telling it to mark the iframe element as focused.
+        if let Some((containing_pipeline_id, subpage_id)) = self.pipeline(pipeline_id).parent_info {
+            let pipeline = self.pipeline(containing_pipeline_id);
+            let ScriptControlChan(ref script_channel) = pipeline.script_chan;
+            let event = ConstellationControlMsg::FocusIFrameMsg(containing_pipeline_id,
+                                                                subpage_id);
+            script_channel.send(event).unwrap();
+
+            self.focus_parent_pipeline(containing_pipeline_id);
+        }
+    }
+
+    fn handle_focus_msg(&mut self, pipeline_id: PipelineId) {
+        self.focus_pipeline_id = Some(pipeline_id);
+
+        // Focus parent iframes recursively
+        self.focus_parent_pipeline(pipeline_id);
+    }
+
     fn add_or_replace_pipeline_in_frame_tree(&mut self, frame_change: FrameChange) {
+
+        // If the currently focused pipeline is the one being changed (or a child
+        // of the pipeline being changed) then update the focus pipeline to be
+        // the replacement.
+        if let Some(old_pipeline_id) = frame_change.old_pipeline_id {
+            let old_frame_id = *self.pipeline_to_frame_map.get(&old_pipeline_id).unwrap();
+            if self.focused_pipeline_in_tree(old_frame_id) {
+                self.focus_pipeline_id = Some(frame_change.new_pipeline_id);
+            }
+        }
+
         let evicted_frames = match frame_change.old_pipeline_id {
             Some(old_pipeline_id) => {
                 // The new pipeline is replacing an old one.
@@ -923,8 +981,20 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
         }
     }
 
+    fn focused_pipeline_in_tree(&self, frame_id: FrameId) -> bool {
+        self.focus_pipeline_id.map_or(false, |pipeline_id| {
+            self.pipeline_exists_in_tree(pipeline_id, Some(frame_id))
+        })
+    }
+
     fn pipeline_is_in_current_frame(&self, pipeline_id: PipelineId) -> bool {
-        self.current_frame_tree_iter(self.root_frame_id)
+        self.pipeline_exists_in_tree(pipeline_id, self.root_frame_id)
+    }
+
+    fn pipeline_exists_in_tree(&self,
+                               pipeline_id: PipelineId,
+                               root_frame_id: Option<FrameId>) -> bool {
+        self.current_frame_tree_iter(root_frame_id)
             .any(|current_frame| current_frame.current == pipeline_id)
     }
 
diff --git a/components/msg/constellation_msg.rs b/components/msg/constellation_msg.rs
index 2097d658b0f..0f911a7e523 100644
--- a/components/msg/constellation_msg.rs
+++ b/components/msg/constellation_msg.rs
@@ -194,6 +194,13 @@ bitflags! {
     }
 }
 
+/// Specifies the type of focus event that is sent to a pipeline
+#[derive(Copy, PartialEq)]
+pub enum FocusType {
+    Element,    // The first focus message - focus the element itself
+    Parent,     // Focusing a parent element (an iframe)
+}
+
 /// Messages from the compositor and script to the constellation.
 pub enum Msg {
     Exit,
@@ -219,7 +226,9 @@ pub enum Msg {
     /// Requests that the constellation instruct layout to begin a new tick of the animation.
     TickAnimation(PipelineId),
     // Request that the constellation send the current root pipeline id over a provided channel
-    GetRootPipeline(Sender<Option<PipelineId>>)
+    GetRootPipeline(Sender<Option<PipelineId>>),
+    /// Notifies the constellation that this frame has received focus.
+    FocusMsg(PipelineId),
 }
 
 // https://developer.mozilla.org/en-US/docs/Web/API/Using_the_Browser_API#Events
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 3fc82215167..aa360edd3a3 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -64,7 +64,7 @@ use dom::window::{Window, WindowHelpers, ReflowReason};
 use layout_interface::{HitTestResponse, MouseOverResponse};
 use msg::compositor_msg::ScriptListener;
 use msg::constellation_msg::Msg as ConstellationMsg;
-use msg::constellation_msg::{ConstellationChan, Key, KeyState, KeyModifiers, MozBrowserEvent};
+use msg::constellation_msg::{ConstellationChan, FocusType, Key, KeyState, KeyModifiers, MozBrowserEvent};
 use msg::constellation_msg::{SUPER, ALT, SHIFT, CONTROL};
 use net_traits::CookieSource::NonHTTP;
 use net_traits::ControlMsg::{SetCookiesForUrl, GetCookiesForUrl};
@@ -216,7 +216,7 @@ pub trait DocumentHelpers<'a> {
     fn is_scripting_enabled(self) -> bool;
     fn begin_focus_transaction(self);
     fn request_focus(self, elem: JSRef<Element>);
-    fn commit_focus_transaction(self);
+    fn commit_focus_transaction(self, focus_type: FocusType);
     fn title_changed(self);
     fn send_title_to_compositor(self);
     fn dirty_all_nodes(self);
@@ -460,7 +460,7 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
 
     /// Reassign the focus context to the element that last requested focus during this
     /// transaction, or none if no elements requested it.
-    fn commit_focus_transaction(self) {
+    fn commit_focus_transaction(self, focus_type: FocusType) {
         //TODO: dispatch blur, focus, focusout, and focusin events
 
         if let Some(ref elem) = self.focused.get().root() {
@@ -473,9 +473,16 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
         if let Some(ref elem) = self.focused.get().root() {
             let node: JSRef<Node> = NodeCast::from_ref(elem.r());
             node.set_focus_state(true);
+
+            // Update the focus state for all elements in the focus chain.
+            // https://html.spec.whatwg.org/multipage/#focus-chain
+            if focus_type == FocusType::Element {
+                let window = self.window.root();
+                let ConstellationChan(ref chan) = window.r().constellation_chan();
+                let event = ConstellationMsg::FocusMsg(window.r().pipeline());
+                chan.send(event).unwrap();
+            }
         }
-        // TODO: Update the focus state for all elements in the focus chain.
-        // https://html.spec.whatwg.org/multipage/#focus-chain
     }
 
     /// Handles any updates when the document's title has changed.
@@ -555,7 +562,7 @@ impl<'a> DocumentHelpers<'a> for JSRef<'a, Document> {
         // https://html.spec.whatwg.org/multipage/#run-authentic-click-activation-steps
         el.r().authentic_click_activation(event);
 
-        self.commit_focus_transaction();
+        self.commit_focus_transaction(FocusType::Element);
         window.r().reflow(ReflowGoal::ForDisplay, ReflowQueryType::NoQuery, ReflowReason::MouseEvent);
     }
 
diff --git a/components/script/dom/htmlelement.rs b/components/script/dom/htmlelement.rs
index 84f1d698cdf..68c097158dc 100644
--- a/components/script/dom/htmlelement.rs
+++ b/components/script/dom/htmlelement.rs
@@ -28,6 +28,7 @@ use dom::node::{Node, NodeHelpers, NodeTypeId, document_from_node, window_from_n
 use dom::virtualmethods::VirtualMethods;
 use dom::window::WindowHelpers;
 
+use msg::constellation_msg::FocusType;
 use util::str::DOMString;
 
 use string_cache::Atom;
@@ -145,7 +146,7 @@ impl<'a> HTMLElementMethods for JSRef<'a, HTMLElement> {
         let document = document.r();
         document.begin_focus_transaction();
         document.request_focus(element);
-        document.commit_focus_transaction();
+        document.commit_focus_transaction(FocusType::Element);
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-blur
@@ -159,7 +160,7 @@ impl<'a> HTMLElementMethods for JSRef<'a, HTMLElement> {
         let document = document_from_node(self).root();
         document.r().begin_focus_transaction();
         // If `request_focus` is not called, focus will be set to None.
-        document.r().commit_focus_transaction();
+        document.r().commit_focus_transaction(FocusType::Element);
     }
 }
 
diff --git a/components/script/script_task.rs b/components/script/script_task.rs
index 4956e810d0f..c9c51eaeb9b 100644
--- a/components/script/script_task.rs
+++ b/components/script/script_task.rs
@@ -24,7 +24,7 @@ use dom::bindings::codegen::Bindings::DocumentBinding::{DocumentMethods, Documen
 use dom::bindings::codegen::InheritTypes::{ElementCast, EventTargetCast, HTMLIFrameElementCast, NodeCast, EventCast};
 use dom::bindings::conversions::FromJSValConvertible;
 use dom::bindings::conversions::StringificationBehavior;
-use dom::bindings::js::{JS, JSRef, OptionalRootable, RootedReference};
+use dom::bindings::js::{JS, JSRef, Temporary, OptionalRootable, RootedReference};
 use dom::bindings::js::{RootCollection, RootCollectionPtr};
 use dom::bindings::refcounted::{LiveDOMReferences, Trusted, TrustedReference};
 use dom::bindings::structuredclone::StructuredCloneData;
@@ -33,7 +33,7 @@ use dom::bindings::utils::{wrap_for_same_compartment, pre_wrap};
 use dom::document::{Document, IsHTMLDocument, DocumentHelpers, DocumentProgressHandler, DocumentProgressTask, DocumentSource};
 use dom::element::{Element, AttributeHandlers};
 use dom::event::{Event, EventHelpers, EventBubbles, EventCancelable};
-use dom::htmliframeelement::HTMLIFrameElementHelpers;
+use dom::htmliframeelement::{HTMLIFrameElement, HTMLIFrameElementHelpers};
 use dom::uievent::UIEvent;
 use dom::eventtarget::EventTarget;
 use dom::node::{self, Node, NodeHelpers, NodeDamage, window_from_node};
@@ -58,7 +58,7 @@ use script_traits::{ConstellationControlMsg, ScriptControlChan};
 use script_traits::ScriptTaskFactory;
 use msg::compositor_msg::ReadyState::{FinishedLoading, Loading, PerformingLayout};
 use msg::compositor_msg::{LayerId, ScriptListener};
-use msg::constellation_msg::{ConstellationChan};
+use msg::constellation_msg::{ConstellationChan, FocusType};
 use msg::constellation_msg::{LoadData, PipelineId, SubpageId, MozBrowserEvent, WorkerId};
 use msg::constellation_msg::{Failure, WindowSizeData, PipelineExitType};
 use msg::constellation_msg::Msg as ConstellationMsg;
@@ -694,6 +694,8 @@ impl ScriptTask {
                                                      old_subpage_id,
                                                      new_subpage_id) =>
                 self.handle_update_subpage_id(containing_pipeline_id, old_subpage_id, new_subpage_id),
+            ConstellationControlMsg::FocusIFrameMsg(containing_pipeline_id, subpage_id) =>
+                self.handle_focus_iframe_msg(containing_pipeline_id, subpage_id),
         }
     }
 
@@ -841,6 +843,23 @@ impl ScriptTask {
         window.r().thaw();
     }
 
+    fn handle_focus_iframe_msg(&self,
+                               parent_pipeline_id: PipelineId,
+                               subpage_id: SubpageId) {
+        let borrowed_page = self.root_page();
+        let page = borrowed_page.find(parent_pipeline_id).unwrap();
+
+        let doc = page.document().root();
+        let frame_element = self.find_iframe(doc.r(), subpage_id).root();
+
+        if let Some(frame_element) = frame_element {
+            let element: JSRef<Element> = ElementCast::from_ref(frame_element.r());
+            doc.r().begin_focus_transaction();
+            doc.r().request_focus(element);
+            doc.r().commit_focus_transaction(FocusType::Parent);
+        }
+    }
+
     /// Handles a mozbrowser event, for example see:
     /// https://developer.mozilla.org/en-US/docs/Web/Events/mozbrowserloadstart
     fn handle_mozbrowser_event_msg(&self,
@@ -851,11 +870,7 @@ impl ScriptTask {
 
         let frame_element = borrowed_page.find(parent_pipeline_id).and_then(|page| {
             let doc = page.document().root();
-            let doc: JSRef<Node> = NodeCast::from_ref(doc.r());
-
-            doc.traverse_preorder()
-               .filter_map(HTMLIFrameElementCast::to_temporary)
-               .find(|node| node.root().r().subpage_id() == Some(subpage_id))
+            self.find_iframe(doc.r(), subpage_id)
         }).root();
 
         if let Some(frame_element) = frame_element {
@@ -871,11 +886,7 @@ impl ScriptTask {
 
         let frame_element = borrowed_page.find(containing_pipeline_id).and_then(|page| {
             let doc = page.document().root();
-            let doc: JSRef<Node> = NodeCast::from_ref(doc.r());
-
-            doc.traverse_preorder()
-               .filter_map(HTMLIFrameElementCast::to_temporary)
-               .find(|node| node.root().r().subpage_id() == Some(old_subpage_id))
+            self.find_iframe(doc.r(), old_subpage_id)
         }).root();
 
         frame_element.unwrap().r().update_subpage_id(new_subpage_id);
@@ -990,12 +1001,7 @@ impl ScriptTask {
             borrowed_page.as_ref().and_then(|borrowed_page| {
                 borrowed_page.find(parent_id).and_then(|page| {
                     let doc = page.document().root();
-                    let doc: JSRef<Node> = NodeCast::from_ref(doc.r());
-
-                    doc.traverse_preorder()
-                       .filter_map(HTMLIFrameElementCast::to_temporary)
-                       .find(|node| node.root().r().subpage_id() == Some(subpage_id))
-                       .map(ElementCast::from_temporary)
+                    self.find_iframe(doc.r(), subpage_id)
                 })
             })
         }).root();
@@ -1094,7 +1100,8 @@ impl ScriptTask {
                                      last_modified,
                                      DocumentSource::FromParser).root();
 
-        window.r().init_browser_context(document.r(), frame_element.r());
+        let frame_element = frame_element.r().map(|elem| ElementCast::from_ref(elem));
+        window.r().init_browser_context(document.r(), frame_element);
 
         // Create the root frame
         page.set_frame(Some(Frame {
@@ -1186,6 +1193,16 @@ impl ScriptTask {
         window.r().reflow(ReflowGoal::ForDisplay, ReflowQueryType::NoQuery, reason);
     }
 
+    /// Find an iframe element in a provided document.
+    fn find_iframe(&self, doc: JSRef<Document>, subpage_id: SubpageId)
+                   -> Option<Temporary<HTMLIFrameElement>> {
+        let doc: JSRef<Node> = NodeCast::from_ref(doc);
+
+        doc.traverse_preorder()
+            .filter_map(HTMLIFrameElementCast::to_temporary)
+            .find(|node| node.root().r().subpage_id() == Some(subpage_id))
+    }
+
     /// This is the main entry point for receiving and dispatching DOM events.
     ///
     /// TODO: Actually perform DOM event dispatch.
@@ -1272,11 +1289,7 @@ impl ScriptTask {
                 let borrowed_page = self.root_page();
                 let iframe = borrowed_page.find(pipeline_id).and_then(|page| {
                     let doc = page.document().root();
-                    let doc: JSRef<Node> = NodeCast::from_ref(doc.r());
-
-                    doc.traverse_preorder()
-                       .filter_map(HTMLIFrameElementCast::to_temporary)
-                       .find(|node| node.root().r().subpage_id() == Some(subpage_id))
+                    self.find_iframe(doc.r(), subpage_id)
                 }).root();
                 if let Some(iframe) = iframe.r() {
                     iframe.navigate_child_browsing_context(load_data.url);
diff --git a/components/script_traits/lib.rs b/components/script_traits/lib.rs
index 57ceb73f2b3..a21a6ae3d1f 100644
--- a/components/script_traits/lib.rs
+++ b/components/script_traits/lib.rs
@@ -74,6 +74,8 @@ pub enum ConstellationControlMsg {
     MozBrowserEventMsg(PipelineId, SubpageId, MozBrowserEvent),
     /// Updates the current subpage id of a given iframe
     UpdateSubpageId(PipelineId, SubpageId, SubpageId),
+    /// Set an iframe to be focused. Used when an element in an iframe gains focus.
+    FocusIFrameMsg(PipelineId, SubpageId),
 }
 
 /// The mouse button involved in the event.