Bug 1524106 - Disconnect l10n root when destroying the document. r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D18774

--HG--
extra : moz-landing-system : lando

dom/base/Document.cpp

@@ -7498,6 +7498,10 @@ void Document::Destroy() {
 
   mIsGoingAway = true;
 
+  if (mDocumentL10n) {
+    mDocumentL10n->Destroy();
+  }
+
   ScriptLoader()->Destroy();
   SetScriptGlobalObject(nullptr);
   RemovedFromDocShell();

intl/l10n/DocumentL10n.cpp

@@ -112,6 +112,15 @@ bool DocumentL10n::Init(nsTArray<nsString>& aResourceIds) {
   return true;
 }
 
+void DocumentL10n::Destroy() {
+  if (mDOMLocalization) {
+    Element* elem = mDocument->GetDocumentElement();
+    if (elem) {
+      mDOMLocalization->DisconnectRoot(elem);
+    }
+  }
+}
+
 JSObject* DocumentL10n::WrapObject(JSContext* aCx,
                                    JS::Handle<JSObject*> aGivenProto) {
   return DocumentL10n_Binding::Wrap(aCx, this, aGivenProto);

intl/l10n/DocumentL10n.h

@@ -65,6 +65,7 @@ class DocumentL10n final : public nsWrapperCache {
  public:
   explicit DocumentL10n(Document* aDocument);
   bool Init(nsTArray<nsString>& aResourceIds);
+  void Destroy();
 
  protected:
   virtual ~DocumentL10n();

intl/l10n/mozIDOMLocalization.idl

@@ -24,6 +24,7 @@ interface mozIDOMLocalization : nsISupports
   Promise translateElements(in Array<Element> aElements);
 
   void connectRoot(in Element aElement);
+  void disconnectRoot(in Element aElement);
   Promise translateRoots();
   readonly attribute Promise ready;
 };