Bug 862519 - [e10s] Better handling of key commands also handled by content (r=smaug)

browser/base/content/browser.js

@@ -1186,13 +1186,6 @@ var gBrowserInit = {
       WindowsPrefSync.init();
     }
 
-    if (gMultiProcessBrowser) {
-      // Bug 862519 - Backspace doesn't work in electrolysis builds.
-      // We bypass the problem by disabling the backspace-to-go-back command.
-      document.getElementById("cmd_handleBackspace").setAttribute("disabled", true);
-      document.getElementById("key_delete").setAttribute("disabled", true);
-    }
-
     SessionStore.promiseInitialized.then(() => {
       // Bail out if the window has been closed in the meantime.
       if (window.closed) {

dom/ipc/PBrowser.ipdl

@@ -334,6 +334,8 @@ parent:
 
     __delete__();
 
+    ReplyKeyEvent(WidgetKeyboardEvent event);
+
 child:
     /**
      * Notify the remote browser that it has been Show()n on this

dom/ipc/TabChild.cpp

@@ -1932,6 +1932,10 @@ TabChild::RecvRealKeyEvent(const WidgetKeyboardEvent& event)
     mIgnoreKeyPressEvent = status == nsEventStatus_eConsumeNoDefault;
   }
 
+  if (localEvent.mFlags.mWantReplyFromContentProcess) {
+    SendReplyKeyEvent(localEvent);
+  }
+
   return true;
 }
 

dom/ipc/TabParent.cpp

@@ -1192,6 +1192,28 @@ TabParent::GetChildProcessOffset()
            pt, targetFrame->PresContext()->AppUnitsPerDevPixel()));
 }
 
+bool
+TabParent::RecvReplyKeyEvent(const WidgetKeyboardEvent& event)
+{
+  NS_ENSURE_TRUE(mFrameElement, true);
+
+  WidgetKeyboardEvent localEvent(event);
+  // Set mNoCrossProcessBoundaryForwarding to avoid this event from
+  // being infinitely redispatched and forwarded to the child again.
+  localEvent.mFlags.mNoCrossProcessBoundaryForwarding = true;
+
+  // Here we convert the WidgetEvent that we received to an nsIDOMEvent
+  // to be able to dispatch it to the <browser> element as the target element.
+  nsIDocument* doc = mFrameElement->OwnerDoc();
+  nsIPresShell* presShell = doc->GetShell();
+  NS_ENSURE_TRUE(presShell, true);
+  nsPresContext* presContext = presShell->GetPresContext();
+  NS_ENSURE_TRUE(presContext, true);
+
+  EventDispatcher::Dispatch(mFrameElement, presContext, &localEvent);
+  return true;
+}
+
 /**
  * Try to answer query event using cached text.
  *

dom/ipc/TabParent.h

@@ -114,6 +114,7 @@ public:
 
     virtual bool RecvMoveFocus(const bool& aForward) MOZ_OVERRIDE;
     virtual bool RecvEvent(const RemoteDOMEvent& aEvent) MOZ_OVERRIDE;
+    virtual bool RecvReplyKeyEvent(const WidgetKeyboardEvent& event);
     virtual bool RecvPRenderFrameConstructor(PRenderFrameParent* actor) MOZ_OVERRIDE;
     virtual bool RecvInitRenderFrame(PRenderFrameParent* aFrame,
                                      ScrollingBehavior* scrolling,

dom/xbl/nsXBLService.cpp

@@ -585,6 +585,15 @@ nsXBLService::AttachGlobalKeyHandler(EventTarget* aTarget)
   manager->AddEventListenerByType(handler, NS_LITERAL_STRING("keypress"),
                                   TrustedEventsAtSystemGroupBubble());
 
+  // The capturing listener is only used for XUL keysets to properly handle
+  // shortcut keys in a multi-process environment.
+  manager->AddEventListenerByType(handler, NS_LITERAL_STRING("keydown"),
+                                  TrustedEventsAtSystemGroupCapture());
+  manager->AddEventListenerByType(handler, NS_LITERAL_STRING("keyup"),
+                                  TrustedEventsAtSystemGroupCapture());
+  manager->AddEventListenerByType(handler, NS_LITERAL_STRING("keypress"),
+                                  TrustedEventsAtSystemGroupCapture());
+
   if (contentNode)
     return contentNode->SetProperty(nsGkAtoms::listener,
                                     handler.forget().take(),
@@ -630,6 +639,13 @@ nsXBLService::DetachGlobalKeyHandler(EventTarget* aTarget)
   manager->RemoveEventListenerByType(handler, NS_LITERAL_STRING("keypress"),
                                      TrustedEventsAtSystemGroupBubble());
 
+  manager->RemoveEventListenerByType(handler, NS_LITERAL_STRING("keydown"),
+                                     TrustedEventsAtSystemGroupCapture());
+  manager->RemoveEventListenerByType(handler, NS_LITERAL_STRING("keyup"),
+                                     TrustedEventsAtSystemGroupCapture());
+  manager->RemoveEventListenerByType(handler, NS_LITERAL_STRING("keypress"),
+                                     TrustedEventsAtSystemGroupCapture());
+
   contentNode->DeleteProperty(nsGkAtoms::listener);
 
   return NS_OK;

dom/xbl/nsXBLWindowKeyHandler.cpp

@@ -26,6 +26,7 @@
 #include "mozilla/Preferences.h"
 #include "mozilla/TextEvents.h"
 #include "mozilla/dom/Element.h"
+#include "mozilla/dom/Event.h"
 #include "nsEventStateManager.h"
 #include "nsIEditor.h"
 #include "nsIHTMLEditor.h"
@@ -276,24 +277,23 @@ nsXBLWindowKeyHandler::WalkHandlers(nsIDOMKeyEvent* aKeyEvent, nsIAtom* aEventTy
   nsresult rv = EnsureHandlers();
   NS_ENSURE_SUCCESS(rv, rv);
 
-  nsCOMPtr<Element> el = GetElement();
+  bool isDisabled;
+  nsCOMPtr<Element> el = GetElement(&isDisabled);
   if (!el) {
     if (mUserHandler) {
-      WalkHandlersInternal(aKeyEvent, aEventType, mUserHandler);
+      WalkHandlersInternal(aKeyEvent, aEventType, mUserHandler, true);
       aKeyEvent->GetDefaultPrevented(&prevent);
       if (prevent)
         return NS_OK; // Handled by the user bindings. Our work here is done.
     }
   }
 
-  nsCOMPtr<nsIContent> content = do_QueryInterface(el);
   // skip keysets that are disabled
-  if (content && content->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled,
-                                      nsGkAtoms::_true, eCaseMatters)) {
+  if (el && isDisabled) {
     return NS_OK;
   }
 
-  WalkHandlersInternal(aKeyEvent, aEventType, mHandler);
+  WalkHandlersInternal(aKeyEvent, aEventType, mHandler, true);
 
   return NS_OK;
 }
@@ -304,20 +304,50 @@ nsXBLWindowKeyHandler::HandleEvent(nsIDOMEvent* aEvent)
   nsCOMPtr<nsIDOMKeyEvent> keyEvent(do_QueryInterface(aEvent));
   NS_ENSURE_TRUE(keyEvent, NS_ERROR_INVALID_ARG);
 
+  uint16_t eventPhase;
+  aEvent->GetEventPhase(&eventPhase);
+  if (eventPhase == nsIDOMEvent::CAPTURING_PHASE) {
+    HandleEventOnCapture(keyEvent);
+    return NS_OK;
+  }
+
   nsAutoString eventType;
   aEvent->GetType(eventType);
   nsCOMPtr<nsIAtom> eventTypeAtom = do_GetAtom(eventType);
   NS_ENSURE_TRUE(eventTypeAtom, NS_ERROR_OUT_OF_MEMORY);
 
-  if (!mWeakPtrForElement) {
-    nsCOMPtr<mozilla::dom::Element> originalTarget =
-      do_QueryInterface(aEvent->GetInternalNSEvent()->originalTarget);
-    if (nsEventStateManager::IsRemoteTarget(originalTarget)) {
-      return NS_OK;
-    }
+  return WalkHandlers(keyEvent, eventTypeAtom);
+}
+
+void
+nsXBLWindowKeyHandler::HandleEventOnCapture(nsIDOMKeyEvent* aEvent)
+{
+  WidgetKeyboardEvent* widgetEvent =
+    aEvent->GetInternalNSEvent()->AsKeyboardEvent();
+
+  if (widgetEvent->mFlags.mNoCrossProcessBoundaryForwarding) {
+    return;
   }
 
-  return WalkHandlers(keyEvent, eventTypeAtom);
+  nsCOMPtr<mozilla::dom::Element> originalTarget =
+    do_QueryInterface(aEvent->GetInternalNSEvent()->originalTarget);
+  if (!nsEventStateManager::IsRemoteTarget(originalTarget)) {
+    return;
+  }
+
+  if (!HasHandlerForEvent(aEvent)) {
+    return;
+  }
+
+  // If this event hasn't been marked as mNoCrossProcessBoundaryForwarding
+  // yet, it means it wasn't processed by content. We'll not call any
+  // of the handlers at this moment, and will wait for the event to be
+  // redispatched with mNoCrossProcessBoundaryForwarding = 1 to process it.
+
+  // Inform the child process that this is a event that we want a reply
+  // from.
+  widgetEvent->mFlags.mWantReplyFromContentProcess = 1;
+  aEvent->StopPropagation();
 }
 
 //
@@ -391,29 +421,31 @@ nsXBLWindowKeyHandler::IsHTMLEditableFieldFocused()
 // WalkHandlersInternal and WalkHandlersAndExecute
 //
 // Given a particular DOM event and a pointer to the first handler in the list,
-// scan through the list to find something to handle the event and then make it
-// so.
+// scan through the list to find something to handle the event. If aExecute = true,
+// the handler will be executed; otherwise just return an answer telling if a handler
+// for that event was found.
 //
-nsresult
+bool
 nsXBLWindowKeyHandler::WalkHandlersInternal(nsIDOMKeyEvent* aKeyEvent,
                                             nsIAtom* aEventType, 
-                                            nsXBLPrototypeHandler* aHandler)
+                                            nsXBLPrototypeHandler* aHandler,
+                                            bool aExecute)
 {
   nsAutoTArray<nsShortcutCandidate, 10> accessKeys;
   nsContentUtils::GetAccelKeyCandidates(aKeyEvent, accessKeys);
 
   if (accessKeys.IsEmpty()) {
-    WalkHandlersAndExecute(aKeyEvent, aEventType, aHandler, 0, false);
-    return NS_OK;
+    return WalkHandlersAndExecute(aKeyEvent, aEventType, aHandler,
+                                  0, false, aExecute);
   }
 
   for (uint32_t i = 0; i < accessKeys.Length(); ++i) {
     nsShortcutCandidate &key = accessKeys[i];
     if (WalkHandlersAndExecute(aKeyEvent, aEventType, aHandler,
-                               key.mCharCode, key.mIgnoreShift))
-      return NS_OK;
+                               key.mCharCode, key.mIgnoreShift, aExecute))
+      return true;
   }
-  return NS_OK;
+  return false;
 }
 
 bool
@@ -421,7 +453,8 @@ nsXBLWindowKeyHandler::WalkHandlersAndExecute(nsIDOMKeyEvent* aKeyEvent,
                                               nsIAtom* aEventType,
                                               nsXBLPrototypeHandler* aHandler,
                                               uint32_t aCharCode,
-                                              bool aIgnoreShiftKey)
+                                              bool aIgnoreShiftKey,
+                                              bool aExecute)
 {
   nsresult rv;
 
@@ -491,6 +524,10 @@ nsXBLWindowKeyHandler::WalkHandlersAndExecute(nsIDOMKeyEvent* aKeyEvent,
       piTarget = mTarget;
     }
 
+    if (!aExecute) {
+      return true;
+    }
+
     rv = currHandler->ExecuteHandler(piTarget, aKeyEvent);
     if (NS_SUCCEEDED(rv)) {
       return true;
@@ -500,10 +537,38 @@ nsXBLWindowKeyHandler::WalkHandlersAndExecute(nsIDOMKeyEvent* aKeyEvent,
   return false;
 }
 
+bool
+nsXBLWindowKeyHandler::HasHandlerForEvent(nsIDOMKeyEvent* aEvent)
+{
+  if (!aEvent->InternalDOMEvent()->IsTrusted()) {
+    return false;
+  }
+
+  nsresult rv = EnsureHandlers();
+  NS_ENSURE_SUCCESS(rv, false);
+
+  bool isDisabled;
+  nsCOMPtr<Element> el = GetElement(&isDisabled);
+  if (el && isDisabled) {
+    return false;
+  }
+
+  nsAutoString eventType;
+  aEvent->GetType(eventType);
+  nsCOMPtr<nsIAtom> eventTypeAtom = do_GetAtom(eventType);
+  NS_ENSURE_TRUE(eventTypeAtom, false);
+
+  return WalkHandlersInternal(aEvent, eventTypeAtom, mHandler, false);
+}
+
 already_AddRefed<Element>
-nsXBLWindowKeyHandler::GetElement()
+nsXBLWindowKeyHandler::GetElement(bool* aIsDisabled)
 {
   nsCOMPtr<Element> element = do_QueryReferent(mWeakPtrForElement);
+  if (element && aIsDisabled) {
+    *aIsDisabled = element->AttrValueIs(kNameSpaceID_None, nsGkAtoms::disabled,
+                                        nsGkAtoms::_true, eCaseMatters);
+  }
   return element.forget();
 }
 

dom/xbl/nsXBLWindowKeyHandler.h

@@ -35,14 +35,23 @@ protected:
   nsresult WalkHandlers(nsIDOMKeyEvent* aKeyEvent, nsIAtom* aEventType);
 
   // walk the handlers, looking for one to handle the event
-  nsresult WalkHandlersInternal(nsIDOMKeyEvent* aKeyEvent,
-                                nsIAtom* aEventType, 
-                                nsXBLPrototypeHandler* aHandler);
+  bool WalkHandlersInternal(nsIDOMKeyEvent* aKeyEvent,
+                            nsIAtom* aEventType,
+                            nsXBLPrototypeHandler* aHandler,
+                            bool aExecute);
 
-  // walk the handlers for aEvent, aCharCode and aIgnoreShiftKey
+  // walk the handlers for aEvent, aCharCode and aIgnoreShiftKey. Execute it
+  // if aExecute = true.
   bool WalkHandlersAndExecute(nsIDOMKeyEvent* aKeyEvent, nsIAtom* aEventType,
-                                nsXBLPrototypeHandler* aHandler,
-                                uint32_t aCharCode, bool aIgnoreShiftKey);
+                              nsXBLPrototypeHandler* aHandler,
+                              uint32_t aCharCode, bool aIgnoreShiftKey,
+                              bool aExecute);
+
+  // HandleEvent function for the capturing phase.
+  void HandleEventOnCapture(nsIDOMKeyEvent* aEvent);
+
+  // Check if any handler would handle the given event.
+  bool HasHandlerForEvent(nsIDOMKeyEvent* aEvent);
 
   // lazily load the handlers. Overridden to handle being attached
   // to a particular element rather than the document
@@ -57,8 +66,10 @@ protected:
   bool IsHTMLEditableFieldFocused();
 
   // Returns the element which was passed as a parameter to the constructor,
-  // unless the element has been removed from the document.
-  already_AddRefed<mozilla::dom::Element> GetElement();
+  // unless the element has been removed from the document. Optionally returns
+  // whether the disabled attribute is set on the element (assuming the element
+  // is non-null).
+  already_AddRefed<mozilla::dom::Element> GetElement(bool* aIsDisabled = nullptr);
   // Using weak pointer to the DOM Element.
   nsWeakPtr              mWeakPtrForElement;
   mozilla::dom::EventTarget* mTarget; // weak ref

widget/BasicEvents.h

@@ -553,6 +553,11 @@ public:
   bool    mNoContentDispatch : 1;
   // If mOnlyChromeDispatch is true, the event is dispatched to only chrome.
   bool    mOnlyChromeDispatch : 1;
+  // If mWantReplyFromContentProcess is true, the event will be redispatched
+  // in the parent process after the content process has handled it. Useful
+  // for when the parent process need the know first how the event was used
+  // by content before handling it itself.
+  bool mWantReplyFromContentProcess : 1;
 
   // If the event is being handled in target phase, returns true.
   inline bool InTargetPhase() const