Bug 1500944 - Part 2: Expose WindowGlobal actors to Chrome JS, r=farre

This serves 2 purposes:
1. Provides an object corresponding to an inner window which Chrome JS can hold onto.
2. Provides the object to JS which Chrome JS per-window actors will be attached to.
3. Provides useful information to Chrome JS in the parent process.

Differential Revision: https://phabricator.services.mozilla.com/D9394

docshell/base/BrowsingContext.h

@@ -124,8 +124,8 @@ public:
     nsTArray<RefPtr<BrowsingContext>>& aBrowsingContexts);
 
   nsISupports* GetParentObject() const;
-  virtual JSObject* WrapObject(JSContext* aCx,
-                               JS::Handle<JSObject*> aGivenProto) override;
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
 
   MOZ_DECLARE_WEAKREFERENCE_TYPENAME(BrowsingContext)
   NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(BrowsingContext)

docshell/base/ChromeBrowsingContext.cpp

@@ -63,6 +63,15 @@ ChromeBrowsingContext::Cast(const BrowsingContext* aContext)
   return static_cast<const ChromeBrowsingContext*>(aContext);
 }
 
+void
+ChromeBrowsingContext::GetWindowGlobals(nsTArray<RefPtr<WindowGlobalParent>>& aWindows)
+{
+  aWindows.SetCapacity(mWindowGlobals.Count());
+  for (auto iter = mWindowGlobals.Iter(); !iter.Done(); iter.Next()) {
+    aWindows.AppendElement(iter.Get()->GetKey());
+  }
+}
+
 void
 ChromeBrowsingContext::RegisterWindowGlobal(WindowGlobalParent* aGlobal)
 {
@@ -77,6 +86,13 @@ ChromeBrowsingContext::UnregisterWindowGlobal(WindowGlobalParent* aGlobal)
   mWindowGlobals.RemoveEntry(aGlobal);
 }
 
+JSObject*
+ChromeBrowsingContext::WrapObject(JSContext* aCx,
+                                  JS::Handle<JSObject*> aGivenProto)
+{
+  return ChromeBrowsingContext_Binding::Wrap(aCx, this, aGivenProto);
+}
+
 void
 ChromeBrowsingContext::Traverse(nsCycleCollectionTraversalCallback& cb)
 {

docshell/base/ChromeBrowsingContext.h

@@ -38,10 +38,15 @@ public:
     return mProcessId == aProcessId;
   }
 
+  void GetWindowGlobals(nsTArray<RefPtr<WindowGlobalParent>>& aWindows);
+
   // Called by WindowGlobalParent to register and unregister window globals.
   void RegisterWindowGlobal(WindowGlobalParent* aGlobal);
   void UnregisterWindowGlobal(WindowGlobalParent* aGlobal);
 
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
 protected:
   void Traverse(nsCycleCollectionTraversalCallback& cb);
   void Unlink();

dom/chrome-webidl/BrowsingContext.webidl

@@ -17,3 +17,8 @@ interface BrowsingContext {
 
   readonly attribute BrowsingContext? opener;
 };
+
+[Exposed=Window, ChromeOnly]
+interface ChromeBrowsingContext : BrowsingContext {
+  sequence<WindowGlobalParent> getWindowGlobals();
+};

dom/chrome-webidl/WindowGlobalActors.webidl

@@ -0,0 +1,33 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+interface Principal;
+interface URI;
+interface nsIDocShell;
+
+[Exposed=Window, ChromeOnly]
+interface WindowGlobalParent {
+  readonly attribute boolean isClosed;
+  readonly attribute boolean isInProcess;
+  readonly attribute ChromeBrowsingContext browsingContext;
+
+  // XXX(nika): We would want to expose this, but |FrameLoader| isn't exposed on System.
+  // readonly attribute FrameLoader? rootFrameLoader; // Embedded (browser) only
+
+  readonly attribute WindowGlobalChild? childActor; // in-process only
+
+  // Information about the currently loaded document.
+  readonly attribute Principal documentPrincipal;
+  readonly attribute URI? documentURI;
+};
+
+[Exposed=Window, ChromeOnly]
+interface WindowGlobalChild {
+  readonly attribute boolean isClosed;
+  readonly attribute boolean isInProcess;
+  readonly attribute BrowsingContext browsingContext;
+
+  readonly attribute WindowGlobalParent? parentActor; // in-process only
+};

dom/chrome-webidl/moz.build

@@ -54,6 +54,7 @@ WEBIDL_FILES = [
     'TelemetryStopwatch.webidl',
     'WebExtensionContentScript.webidl',
     'WebExtensionPolicy.webidl',
+    'WindowGlobalActors.webidl',
     'XULFrameElement.webidl',
     'XULMenuElement.webidl',
     'XULScrollElement.webidl',

dom/ipc/WindowGlobalChild.cpp

@@ -7,6 +7,7 @@
 #include "mozilla/dom/WindowGlobalChild.h"
 #include "mozilla/ipc/InProcessChild.h"
 #include "mozilla/dom/BrowsingContext.h"
+#include "mozilla/dom/WindowGlobalActorsBinding.h"
 
 namespace mozilla {
 namespace dom {
@@ -54,7 +55,7 @@ WindowGlobalChild::Create(nsGlobalWindowInner* aWindow)
 }
 
 already_AddRefed<WindowGlobalParent>
-WindowGlobalChild::GetOtherSide()
+WindowGlobalChild::GetParentActor()
 {
   if (mIPCClosed) {
     return nullptr;
@@ -73,7 +74,23 @@ WindowGlobalChild::~WindowGlobalChild()
 {
 }
 
-NS_IMPL_CYCLE_COLLECTION(WindowGlobalChild, mWindowGlobal, mBrowsingContext)
+JSObject*
+WindowGlobalChild::WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto)
+{
+  return WindowGlobalChild_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+nsISupports*
+WindowGlobalChild::GetParentObject()
+{
+  return xpc::NativeGlobal(xpc::PrivilegedJunkScope());
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(WindowGlobalChild,
+                                      mWindowGlobal,
+                                      mBrowsingContext)
+
 NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(WindowGlobalChild, AddRef)
 NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(WindowGlobalChild, Release)
 

dom/ipc/WindowGlobalChild.h

@@ -9,6 +9,7 @@
 
 #include "mozilla/RefPtr.h"
 #include "mozilla/dom/PWindowGlobalChild.h"
+#include "nsWrapperCache.h"
 
 class nsGlobalWindowInner;
 class nsDocShell;
@@ -23,11 +24,12 @@ class WindowGlobalParent;
  * Actor for a single nsGlobalWindowInner. This actor is used to communicate
  * information to the parent process asynchronously.
  */
-class WindowGlobalChild : public PWindowGlobalChild
+class WindowGlobalChild : public nsWrapperCache
+                        , public PWindowGlobalChild
 {
 public:
   NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(WindowGlobalChild)
-  NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(WindowGlobalChild)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(WindowGlobalChild)
 
   dom::BrowsingContext* BrowsingContext() { return mBrowsingContext; }
   nsGlobalWindowInner* WindowGlobal() { return mWindowGlobal; }
@@ -41,12 +43,16 @@ public:
 
   // Get the other side of this actor if it is an in-process actor. Returns
   // |nullptr| if the actor has been torn down, or is not in-process.
-  already_AddRefed<WindowGlobalParent> GetOtherSide();
+  already_AddRefed<WindowGlobalParent> GetParentActor();
 
   // Create and initialize the WindowGlobalChild object.
   static already_AddRefed<WindowGlobalChild>
   Create(nsGlobalWindowInner* aWindow);
 
+  nsISupports* GetParentObject();
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
 protected:
   virtual void ActorDestroy(ActorDestroyReason aWhy) override;
 

dom/ipc/WindowGlobalParent.cpp

@@ -7,6 +7,7 @@
 #include "mozilla/dom/WindowGlobalParent.h"
 #include "mozilla/ipc/InProcessParent.h"
 #include "mozilla/dom/ChromeBrowsingContext.h"
+#include "mozilla/dom/WindowGlobalActorsBinding.h"
 
 using namespace mozilla::ipc;
 
@@ -59,7 +60,7 @@ WindowGlobalParent::Init(const WindowGlobalInit& aInit)
     // In the in-process case, we can get it from the other side's
     // WindowGlobalChild.
     MOZ_ASSERT(Manager()->GetProtocolTypeId() == PInProcessMsgStart);
-    RefPtr<WindowGlobalChild> otherSide = GetOtherSide();
+    RefPtr<WindowGlobalChild> otherSide = GetChildActor();
     if (otherSide && otherSide->WindowGlobal()) {
       // Get the toplevel window from the other side.
       RefPtr<nsDocShell> docShell = nsDocShell::Cast(otherSide->WindowGlobal()->GetDocShell());
@@ -82,7 +83,7 @@ WindowGlobalParent::Init(const WindowGlobalInit& aInit)
 }
 
 already_AddRefed<WindowGlobalChild>
-WindowGlobalParent::GetOtherSide()
+WindowGlobalParent::GetChildActor()
 {
   if (mIPCClosed) {
     return nullptr;
@@ -111,7 +112,23 @@ WindowGlobalParent::~WindowGlobalParent()
 {
 }
 
-NS_IMPL_CYCLE_COLLECTION(WindowGlobalParent, mFrameLoader, mBrowsingContext)
+JSObject*
+WindowGlobalParent::WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto)
+{
+  return WindowGlobalParent_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+nsISupports*
+WindowGlobalParent::GetParentObject()
+{
+  return xpc::NativeGlobal(xpc::PrivilegedJunkScope());
+}
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(WindowGlobalParent,
+                                      mFrameLoader,
+                                      mBrowsingContext)
+
 NS_IMPL_CYCLE_COLLECTION_ROOT_NATIVE(WindowGlobalParent, AddRef)
 NS_IMPL_CYCLE_COLLECTION_UNROOT_NATIVE(WindowGlobalParent, Release)
 

dom/ipc/WindowGlobalParent.h

@@ -9,6 +9,7 @@
 
 #include "mozilla/RefPtr.h"
 #include "mozilla/dom/PWindowGlobalParent.h"
+#include "nsWrapperCache.h"
 
 class nsIPrincipal;
 class nsIURI;
@@ -23,11 +24,12 @@ class WindowGlobalChild;
 /**
  * A handle in the parent process to a specific nsGlobalWindowInner object.
  */
-class WindowGlobalParent final : public PWindowGlobalParent
+class WindowGlobalParent final : public nsWrapperCache
+                               , public PWindowGlobalParent
 {
 public:
   NS_INLINE_DECL_CYCLE_COLLECTING_NATIVE_REFCOUNTING(WindowGlobalParent)
-  NS_DECL_CYCLE_COLLECTION_NATIVE_CLASS(WindowGlobalParent)
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_NATIVE_CLASS(WindowGlobalParent)
 
   // Has this actor been shut down
   bool IsClosed() { return mIPCClosed; }
@@ -38,7 +40,7 @@ public:
 
   // Get the other side of this actor if it is an in-process actor. Returns
   // |nullptr| if the actor has been torn down, or is not in-process.
-  already_AddRefed<WindowGlobalChild> GetOtherSide();
+  already_AddRefed<WindowGlobalChild> GetChildActor();
 
   // The principal of this WindowGlobal. This value will not change over the
   // lifetime of the WindowGlobal object, even to reflect changes in
@@ -65,6 +67,10 @@ public:
   // be called after setting the Manager actor.
   void Init(const WindowGlobalInit& aInit);
 
+  nsISupports* GetParentObject();
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
 protected:
   // IPC messages
   mozilla::ipc::IPCResult RecvUpdateDocumentURI(nsIURI* aURI) override;