Bug 1247687 - Implement InitModuleLoader methods for WorkerScriptLoader and WorkerGlobalScope; r=jonco

This implements a method to initialize the moduleLoader for workers. This will initialize only once, for all worker types (module and classic).

Depends on D147324

Differential Revision: https://phabricator.services.mozilla.com/D147326

dom/workers/ScriptLoader.cpp

@@ -411,8 +411,20 @@ WorkerScriptLoader::WorkerScriptLoader(
   }
 
   nsIGlobalObject* global = GetGlobal();
-
   mController = global->GetController();
+  // Set up the module loader, if it has not been yet.
+  // TODO: Implement this for classic scripts when dynamic imports are added.
+  if (aWorkerPrivate->WorkerType() == WorkerType::Module) {
+    InitModuleLoader();
+  }
+}
+
+void WorkerScriptLoader::InitModuleLoader() {
+  mWorkerRef->Private()->AssertIsOnWorkerThread();
+  RefPtr<WorkerModuleLoader> moduleLoader =
+      new WorkerModuleLoader(this, GetGlobal(), mSyncLoopTarget.get());
+  static_cast<WorkerGlobalScopeBase*>(GetGlobal())
+      ->InitModuleLoader(moduleLoader);
 }
 
 void WorkerScriptLoader::CreateScriptRequests(

dom/workers/ScriptLoader.h

@@ -12,6 +12,7 @@
 #include "mozilla/dom/WorkerCommon.h"
 #include "mozilla/dom/WorkerLoadContext.h"
 #include "mozilla/dom/WorkerRef.h"
+#include "mozilla/dom/workerinternals/WorkerModuleLoader.h"
 #include "mozilla/Maybe.h"
 #include "nsIContentPolicy.h"
 #include "nsStringFwd.h"
@@ -232,6 +233,8 @@ class WorkerScriptLoader : public JS::loader::ScriptLoaderInterface,
     return NS_OK;
   }
 
+  void InitModuleLoader();
+
   void TryShutdown();
 
   nsTArray<RefPtr<ThreadSafeRequestHandle>> GetLoadingList();

dom/workers/WorkerScope.cpp

@@ -260,6 +260,15 @@ JSObject* WorkerGlobalScopeBase::GetGlobalJSObject() {
   return GetWrapper();
 }
 
+void WorkerGlobalScopeBase::NoteTerminating() {
+  if (mModuleLoader) {
+    mModuleLoader->Shutdown();
+    mModuleLoader = nullptr;
+  }
+
+  StartDying();
+}
+
 JSObject* WorkerGlobalScopeBase::GetGlobalJSObjectPreserveColor() const {
   AssertIsOnWorkerThread();
   return GetWrapperPreserveColor();
@@ -440,7 +449,7 @@ void WorkerGlobalScope::NoteTerminating() {
     return;
   }
 
-  StartDying();
+  WorkerGlobalScopeBase::NoteTerminating();
 }
 
 void WorkerGlobalScope::NoteShuttingDown() {

dom/workers/WorkerScope.h

@@ -8,6 +8,7 @@
 #define mozilla_dom_workerscope_h__
 
 #include "js/TypeDecls.h"
+#include "js/loader/ModuleLoaderBase.h"
 #include "mozilla/Assertions.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/DOMEventTargetHelper.h"
@@ -158,8 +159,23 @@ class WorkerGlobalScopeBase : public DOMEventTargetHelper,
 
   Console* GetConsoleIfExists() const { return mConsole; }
 
+  void InitModuleLoader(JS::loader::ModuleLoaderBase* aModuleLoader) {
+    if (!mModuleLoader) {
+      mModuleLoader = aModuleLoader;
+    }
+  }
+
+  // The nullptr here is not used, but is required to make the override method
+  // have the same signature as other GetModuleLoader methods on globals.
+  JS::loader::ModuleLoaderBase* GetModuleLoader(
+      JSContext* aCx = nullptr) override {
+    return mModuleLoader;
+  };
+
   uint64_t WindowID() const;
 
+  virtual void NoteTerminating();
+
   // Usually global scope dies earlier than the WorkerPrivate, but if we see
   // it leak at least we can tell it to not carry away a dead pointer.
   void NoteWorkerTerminated() { mWorkerPrivate = nullptr; }
@@ -184,6 +200,7 @@ class WorkerGlobalScopeBase : public DOMEventTargetHelper,
 
  private:
   RefPtr<Console> mConsole;
+  RefPtr<JS::loader::ModuleLoaderBase> mModuleLoader;
   const UniquePtr<ClientSource> mClientSource;
   nsCOMPtr<nsISerialEventTarget> mSerialEventTarget;
   bool mShouldResistFingerprinting;
@@ -217,7 +234,7 @@ class WorkerGlobalScope : public WorkerGlobalScopeBase {
 
   using WorkerGlobalScopeBase::WorkerGlobalScopeBase;
 
-  void NoteTerminating();
+  void NoteTerminating() override;
 
   void NoteShuttingDown();
 

js/loader/ModuleLoaderBase.cpp

@@ -989,7 +989,9 @@ void ModuleLoaderBase::Shutdown() {
   MOZ_ASSERT(mFetchingModules.IsEmpty());
 
   for (const auto& entry : mFetchedModules) {
-    entry.GetData()->Shutdown();
+    if (entry.GetData()) {
+      entry.GetData()->Shutdown();
+    }
   }
 
   mFetchedModules.Clear();