Bug 1888878 - Extract background actor creation into a separate function; r=dom-storage-reviewers,asuth

Differential Revision: https://phabricator.services.mozilla.com/D206228

dom/indexedDB/IndexedDatabaseManager.cpp

@@ -351,6 +351,30 @@ void IndexedDatabaseManager::Destroy() {
   delete this;
 }
 
+nsresult IndexedDatabaseManager::EnsureBackgroundActor() {
+  if (mBackgroundActor) {
+    return NS_OK;
+  }
+
+  PBackgroundChild* bgActor = BackgroundChild::GetForCurrentThread();
+  if (NS_WARN_IF(!bgActor)) {
+    return NS_ERROR_FAILURE;
+  }
+
+  {
+    BackgroundUtilsChild* actor = new BackgroundUtilsChild(this);
+
+    mBackgroundActor = static_cast<BackgroundUtilsChild*>(
+        bgActor->SendPBackgroundIndexedDBUtilsConstructor(actor));
+
+    if (NS_WARN_IF(!mBackgroundActor)) {
+      return NS_ERROR_FAILURE;
+    }
+  }
+
+  return NS_OK;
+}
+
 // static
 bool IndexedDatabaseManager::ResolveSandboxBinding(JSContext* aCx) {
   MOZ_ASSERT(NS_IsMainThread());
@@ -603,21 +627,7 @@ nsresult IndexedDatabaseManager::BlockAndGetFileReferences(
     return NS_ERROR_UNEXPECTED;
   }
 
-  if (!mBackgroundActor) {
-    PBackgroundChild* bgActor = BackgroundChild::GetForCurrentThread();
-    if (NS_WARN_IF(!bgActor)) {
-      return NS_ERROR_FAILURE;
-    }
-
-    BackgroundUtilsChild* actor = new BackgroundUtilsChild(this);
-
-    mBackgroundActor = static_cast<BackgroundUtilsChild*>(
-        bgActor->SendPBackgroundIndexedDBUtilsConstructor(actor));
-  }
-
-  if (NS_WARN_IF(!mBackgroundActor)) {
-    return NS_ERROR_FAILURE;
-  }
+  QM_TRY(MOZ_TO_RESULT(EnsureBackgroundActor()));
 
   if (!mBackgroundActor->SendGetFileReferences(
           aPersistenceType, nsCString(aOrigin), nsString(aDatabaseName),

dom/indexedDB/IndexedDatabaseManager.h

@@ -153,6 +153,8 @@ class IndexedDatabaseManager final : public nsIIndexedDatabaseManager {
 
   void Destroy();
 
+  nsresult EnsureBackgroundActor();
+
   static void LoggingModePrefChangedCallback(const char* aPrefName,
                                              void* aClosure);