Bug 1617170 - Make FileInfo more testable by removing the dependency on FileManager. r=dom-workers-and-storage-reviewers,janv

Also removes the dependency of FileManager(Base)/FileInfo on
IndexedDatabaseManager, based on contributions by janv@mozilla.com

Differential Revision: https://phabricator.services.mozilla.com/D64347

dom/indexedDB/ActorsParent.cpp

@@ -10,7 +10,6 @@
 #include <numeric>
 #include <stdint.h>  // UINTPTR_MAX, uintptr_t
 #include <utility>
-#include "FileInfo.h"
 #include "FileManager.h"
 #include "IDBCursorType.h"
 #include "IDBObjectStore.h"
@@ -16456,6 +16455,8 @@ mozilla::ipc::IPCResult Cursor<CursorType>::RecvContinue(
  * FileManager
  ******************************************************************************/
 
+FileManager::MutexType FileManager::sMutex;
+
 FileManager::FileManager(PersistenceType aPersistenceType,
                          const nsACString& aGroup, const nsACString& aOrigin,
                          const nsAString& aDatabaseName, bool aEnforcingQuota)
@@ -16566,7 +16567,8 @@ nsresult FileManager::Init(nsIFile* aDirectory,
     // 0, but the dbRefCnt is non-zero, which will keep the FileInfo object
     // alive.
     MOZ_ASSERT(dbRefCnt > 0);
-    mFileInfos.Put(id, new FileInfo(this, id, static_cast<nsrefcnt>(dbRefCnt)));
+    mFileInfos.Put(id, new FileInfo(FileManagerGuard{}, this, id,
+                                    static_cast<nsrefcnt>(dbRefCnt)));
 
     mLastFileId = std::max(id, mLastFileId);
   }

dom/indexedDB/FileInfo.cpp

@@ -4,141 +4,14 @@
  * 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/. */
 
-#include "FileInfo.h"
-
-#include "ActorsParent.h"
+#include "FileInfoTImpl.h"
 #include "FileManager.h"
-#include "IndexedDatabaseManager.h"
-#include "mozilla/Assertions.h"
-#include "mozilla/Attributes.h"
-#include "mozilla/Mutex.h"
-#include "mozilla/dom/quota/QuotaManager.h"
-#include "mozilla/ipc/BackgroundParent.h"
-#include "nsError.h"
-#include "nsThreadUtils.h"
 
 namespace mozilla {
 namespace dom {
 namespace indexedDB {
 
-using namespace mozilla::dom::quota;
-using namespace mozilla::ipc;
-
-void FileInfo::GetReferences(int32_t* aRefCnt, int32_t* aDBRefCnt,
-                             int32_t* aSliceRefCnt) {
-  MOZ_ASSERT(!IndexedDatabaseManager::IsClosed());
-
-  MutexAutoLock lock(IndexedDatabaseManager::FileMutex());
-
-  if (aRefCnt) {
-    *aRefCnt = mRefCnt;
-  }
-
-  if (aDBRefCnt) {
-    *aDBRefCnt = mDBRefCnt;
-  }
-
-  if (aSliceRefCnt) {
-    *aSliceRefCnt = mSliceRefCnt;
-  }
-}
-
-void FileInfo::UpdateReferences(ThreadSafeAutoRefCnt& aRefCount, int32_t aDelta,
-                                bool aSyncDeleteFile) {
-  // XXX This can go away once DOM objects no longer hold FileInfo objects...
-  //     Looking at you, BlobImplBase...
-  //     BlobImplBase is being addressed in bug 1068975.
-  if (IndexedDatabaseManager::IsClosed()) {
-    MOZ_ASSERT(&aRefCount == &mRefCnt);
-    MOZ_ASSERT(aDelta == 1 || aDelta == -1);
-
-    if (aDelta > 0) {
-      ++aRefCount;
-    } else {
-      nsrefcnt count = --aRefCount;
-      if (!count) {
-        mRefCnt = 1;
-        delete this;
-      }
-    }
-    return;
-  }
-
-  MOZ_ASSERT(!IndexedDatabaseManager::IsClosed());
-
-  bool needsCleanup;
-  {
-    MutexAutoLock lock(IndexedDatabaseManager::FileMutex());
-
-    aRefCount = aRefCount + aDelta;
-
-    if (mRefCnt + mDBRefCnt + mSliceRefCnt > 0) {
-      return;
-    }
-
-    mFileManager->RemoveFileInfo(Id(), lock);
-
-    needsCleanup = !mFileManager->Invalidated();
-  }
-
-  if (needsCleanup) {
-    if (aSyncDeleteFile) {
-      nsresult rv = mFileManager->SyncDeleteFile(Id());
-      if (NS_FAILED(rv)) {
-        NS_WARNING("FileManager cleanup failed!");
-      }
-    } else {
-      Cleanup();
-    }
-  }
-
-  delete this;
-}
-
-bool FileInfo::LockedClearDBRefs() {
-  MOZ_ASSERT(!IndexedDatabaseManager::IsClosed());
-
-  IndexedDatabaseManager::FileMutex().AssertCurrentThreadOwns();
-
-  mDBRefCnt = 0;
-
-  if (mRefCnt || mSliceRefCnt) {
-    return true;
-  }
-
-  // In this case, we are not responsible for removing the file info from the
-  // hashtable. It's up to FileManager which is the only caller of this method.
-
-  MOZ_ASSERT(mFileManager->Invalidated());
-
-  delete this;
-
-  return false;
-}
-
-void FileInfo::Cleanup() {
-  AssertIsOnBackgroundThread();
-
-  int64_t id = Id();
-
-  if (NS_FAILED(mFileManager->AsyncDeleteFile(id))) {
-    NS_WARNING("Failed to delete file asynchronously!");
-  }
-}
-
-nsCOMPtr<nsIFile> FileInfo::GetFileForFileInfo() const {
-  const nsCOMPtr<nsIFile> directory = Manager()->GetDirectory();
-  if (NS_WARN_IF(!directory)) {
-    return nullptr;
-  }
-
-  nsCOMPtr<nsIFile> file = FileManager::GetFileForId(directory, Id());
-  if (NS_WARN_IF(!file)) {
-    return nullptr;
-  }
-
-  return file;
-}
+template class FileInfoT<FileManager>;
 
 }  // namespace indexedDB
 }  // namespace dom

dom/indexedDB/FileInfo.h

@@ -1,74 +0,0 @@
-/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
-/* vim: set ts=8 sts=2 et sw=2 tw=80: */
-/* 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/. */
-
-#ifndef mozilla_dom_indexeddb_fileinfo_h__
-#define mozilla_dom_indexeddb_fileinfo_h__
-
-#include "nsISupportsImpl.h"
-
-namespace mozilla {
-namespace dom {
-namespace indexedDB {
-
-class FileManager;
-
-class FileInfo final {
-  template <typename FileManager, typename IndexedDatabaseManager>
-  friend class FileManagerBase;
-
-  const int64_t mFileId;
-
-  ThreadSafeAutoRefCnt mRefCnt;
-  ThreadSafeAutoRefCnt mDBRefCnt;
-  ThreadSafeAutoRefCnt mSliceRefCnt;
-
-  const RefPtr<FileManager> mFileManager;
-
- public:
-  FileInfo(RefPtr<FileManager> aFileManager, const int64_t aFileId,
-           const nsrefcnt aInitialDBRefCnt = 0)
-      : mFileId(aFileId),
-        mDBRefCnt(aInitialDBRefCnt),
-        mFileManager(std::move(aFileManager)) {
-    MOZ_ASSERT(mFileManager);
-    MOZ_ASSERT(mFileId > 0);
-  }
-
-  void AddRef() { UpdateReferences(mRefCnt, 1); }
-
-  void Release(const bool aSyncDeleteFile = false) {
-    UpdateReferences(mRefCnt, -1, aSyncDeleteFile);
-  }
-
-  void UpdateDBRefs(int32_t aDelta) { UpdateReferences(mDBRefCnt, aDelta); }
-
-  void UpdateSliceRefs(int32_t aDelta) {
-    UpdateReferences(mSliceRefCnt, aDelta);
-  }
-
-  void GetReferences(int32_t* aRefCnt, int32_t* aDBRefCnt,
-                     int32_t* aSliceRefCnt);
-
-  FileManager* Manager() const { return mFileManager; }
-
-  int64_t Id() const { return mFileId; }
-
-  nsCOMPtr<nsIFile> GetFileForFileInfo() const;
-
- private:
-  void UpdateReferences(ThreadSafeAutoRefCnt& aRefCount, int32_t aDelta,
-                        bool aSyncDeleteFile = false);
-
-  bool LockedClearDBRefs();
-
-  void Cleanup();
-};
-
-}  // namespace indexedDB
-}  // namespace dom
-}  // namespace mozilla
-
-#endif  // mozilla_dom_indexeddb_fileinfo_h__

dom/indexedDB/FileInfoFwd.h

@@ -0,0 +1,20 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_dom_indexeddb_fileinfofwd_h__
+#define mozilla_dom_indexeddb_fileinfofwd_h__
+
+namespace mozilla::dom::indexedDB {
+
+class FileManager;
+template <typename FileManager>
+class FileInfoT;
+
+using FileInfo = FileInfoT<indexedDB::FileManager>;
+
+}  // namespace mozilla::dom::indexedDB
+
+#endif  // mozilla_dom_indexeddb_fileinfofwd_h__

dom/indexedDB/FileInfoT.h

@@ -0,0 +1,62 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_dom_indexeddb_fileinfot_h__
+#define mozilla_dom_indexeddb_fileinfot_h__
+
+#include "nsISupportsImpl.h"
+#include "nsCOMPtr.h"
+
+namespace mozilla {
+namespace dom {
+namespace indexedDB {
+
+template <typename FileManager>
+class FileInfoT final {
+ public:
+  using AutoLock = typename FileManager::AutoLock;
+
+  FileInfoT(const typename FileManager::FileManagerGuard& aGuard,
+            RefPtr<FileManager> aFileManager, const int64_t aFileId,
+            const nsrefcnt aInitialDBRefCnt = 0);
+
+  void AddRef();
+  void Release(const bool aSyncDeleteFile = false);
+
+  void UpdateDBRefs(int32_t aDelta);
+  void UpdateSliceRefs(int32_t aDelta);
+
+  void GetReferences(int32_t* aRefCnt, int32_t* aDBRefCnt,
+                     int32_t* aSliceRefCnt);
+
+  FileManager* Manager() const;
+
+  int64_t Id() const;
+
+  nsCOMPtr<nsIFile> GetFileForFileInfo() const;
+
+  bool LockedClearDBRefs(const typename FileManager::FileManagerGuard& aGuard);
+
+ private:
+  void UpdateReferences(ThreadSafeAutoRefCnt& aRefCount, int32_t aDelta,
+                        bool aSyncDeleteFile = false);
+
+  void Cleanup();
+
+  const int64_t mFileId;
+
+  ThreadSafeAutoRefCnt mRefCnt;
+  ThreadSafeAutoRefCnt mDBRefCnt;
+  ThreadSafeAutoRefCnt mSliceRefCnt;
+
+  const RefPtr<FileManager> mFileManager;
+};
+
+}  // namespace indexedDB
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_indexeddb_fileinfot_h__

dom/indexedDB/FileInfoTImpl.h

@@ -0,0 +1,162 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_dom_indexeddb_fileinfotimpl_h__
+#define mozilla_dom_indexeddb_fileinfotimpl_h__
+
+#include "FileInfoT.h"
+
+#include "mozilla/Mutex.h"
+#include "nsIFile.h"
+
+namespace mozilla {
+namespace dom {
+namespace indexedDB {
+
+template <typename FileManager>
+FileInfoT<FileManager>::FileInfoT(
+    const typename FileManager::FileManagerGuard& aGuard,
+    RefPtr<FileManager> aFileManager, const int64_t aFileId,
+    const nsrefcnt aInitialDBRefCnt)
+    : mFileId(aFileId),
+      mDBRefCnt(aInitialDBRefCnt),
+      mFileManager(std::move(aFileManager)) {
+  MOZ_ASSERT(mFileId > 0);
+  MOZ_ASSERT(mFileManager);
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::AddRef() {
+  UpdateReferences(mRefCnt, 1);
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::Release(const bool aSyncDeleteFile) {
+  UpdateReferences(mRefCnt, -1, aSyncDeleteFile);
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::UpdateDBRefs(int32_t aDelta) {
+  UpdateReferences(mDBRefCnt, aDelta);
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::UpdateSliceRefs(int32_t aDelta) {
+  UpdateReferences(mSliceRefCnt, aDelta);
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::GetReferences(int32_t* const aRefCnt,
+                                           int32_t* const aDBRefCnt,
+                                           int32_t* const aSliceRefCnt) {
+  AutoLock lock(FileManager::Mutex());
+
+  if (aRefCnt) {
+    *aRefCnt = mRefCnt;
+  }
+
+  if (aDBRefCnt) {
+    *aDBRefCnt = mDBRefCnt;
+  }
+
+  if (aSliceRefCnt) {
+    *aSliceRefCnt = mSliceRefCnt;
+  }
+}
+
+template <typename FileManager>
+FileManager* FileInfoT<FileManager>::Manager() const {
+  return mFileManager;
+}
+
+template <typename FileManager>
+int64_t FileInfoT<FileManager>::Id() const {
+  return mFileId;
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::UpdateReferences(ThreadSafeAutoRefCnt& aRefCount,
+                                              const int32_t aDelta,
+                                              const bool aSyncDeleteFile) {
+  bool needsCleanup;
+  {
+    AutoLock lock(FileManager::Mutex());
+
+    aRefCount = aRefCount + aDelta;
+
+    if (mRefCnt + mDBRefCnt + mSliceRefCnt > 0) {
+      return;
+    }
+
+    mFileManager->RemoveFileInfo(Id(), lock);
+
+    needsCleanup = !mFileManager->Invalidated();
+  }
+
+  if (needsCleanup) {
+    if (aSyncDeleteFile) {
+      nsresult rv = mFileManager->SyncDeleteFile(Id());
+      if (NS_FAILED(rv)) {
+        NS_WARNING("FileManager cleanup failed!");
+      }
+    } else {
+      Cleanup();
+    }
+  }
+
+  delete this;
+}
+
+template <typename FileManager>
+bool FileInfoT<FileManager>::LockedClearDBRefs(
+    const typename FileManager::FileManagerGuard&) {
+  FileManager::Mutex().AssertCurrentThreadOwns();
+
+  mDBRefCnt = 0;
+
+  if (mRefCnt || mSliceRefCnt) {
+    return true;
+  }
+
+  // In this case, we are not responsible for removing the file info from the
+  // hashtable. It's up to FileManager which is the only caller of this method.
+
+  MOZ_ASSERT(mFileManager->Invalidated());
+
+  delete this;
+
+  return false;
+}
+
+template <typename FileManager>
+void FileInfoT<FileManager>::Cleanup() {
+  int64_t id = Id();
+
+  if (NS_FAILED(mFileManager->AsyncDeleteFile(id))) {
+    NS_WARNING("Failed to delete file asynchronously!");
+  }
+}
+
+template <typename FileManager>
+nsCOMPtr<nsIFile> FileInfoT<FileManager>::GetFileForFileInfo() const {
+  const nsCOMPtr<nsIFile> directory = Manager()->GetDirectory();
+  if (NS_WARN_IF(!directory)) {
+    return nullptr;
+  }
+
+  nsCOMPtr<nsIFile> file = FileManager::GetFileForId(directory, Id());
+  if (NS_WARN_IF(!file)) {
+    return nullptr;
+  }
+
+  return file;
+}
+
+}  // namespace indexedDB
+}  // namespace dom
+}  // namespace mozilla
+
+#endif  // mozilla_dom_indexeddb_fileinfotimpl_h__

dom/indexedDB/FileManager.h

@@ -9,7 +9,6 @@
 
 #include "mozilla/dom/quota/PersistenceType.h"
 #include "FileManagerBase.h"
-#include "IndexedDatabaseManager.h"
 #include "InitializedOnce.h"
 
 class nsIFile;
@@ -20,9 +19,9 @@ namespace dom {
 namespace indexedDB {
 
 // Implemented in ActorsParent.cpp.
-class FileManager final
-    : public FileManagerBase<FileManager, dom::IndexedDatabaseManager> {
-  typedef mozilla::dom::quota::PersistenceType PersistenceType;
+class FileManager final : public FileManagerBase<FileManager> {
+  using PersistenceType = mozilla::dom::quota::PersistenceType;
+  using FileManagerBase<FileManager>::MutexType;
 
   const PersistenceType mPersistenceType;
   const nsCString mGroup;
@@ -34,6 +33,11 @@ class FileManager final
 
   const bool mEnforcingQuota;
 
+  // Lock protecting FileManager.mFileInfos.
+  // It's s also used to atomically update FileInfo.mRefCnt and
+  // FileInfo.mDBRefCnt
+  static MutexType sMutex;
+
  public:
   static MOZ_MUST_USE nsCOMPtr<nsIFile> GetFileForId(nsIFile* aDirectory,
                                                      int64_t aId);
@@ -79,6 +83,8 @@ class FileManager final
 
   NS_INLINE_DECL_THREADSAFE_REFCOUNTING(FileManager)
 
+  static StaticMutex& Mutex() { return sMutex; }
+
  private:
   ~FileManager() = default;
 };

dom/indexedDB/FileManagerBase.h

@@ -9,36 +9,31 @@
 
 #include "mozilla/Attributes.h"
 #include "mozilla/Mutex.h"
+#include "mozilla/StaticMutex.h"
 #include "nsDataHashtable.h"
 #include "nsHashKeys.h"
 #include "nsISupportsImpl.h"
+#include "FileInfoT.h"
 #include "FlippedOnce.h"
 
 namespace mozilla {
 namespace dom {
 namespace indexedDB {
 
-class FileInfo;
-
-template <typename FileManager, typename IndexedDatabaseManager>
+template <typename FileManager>
 class FileManagerBase {
  public:
-  using FileInfo = indexedDB::FileInfo;
-  using MutexType = decltype(IndexedDatabaseManager::FileMutex());
-  using AutoLock = mozilla::detail::BaseAutoLock<MutexType>;
+  using FileInfo = FileInfoT<FileManager>;
+  using MutexType = StaticMutex;
+  using AutoLock = mozilla::detail::BaseAutoLock<MutexType&>;
 
   MOZ_MUST_USE RefPtr<FileInfo> GetFileInfo(int64_t aId) const {
-    if (IndexedDatabaseManager::IsClosed()) {
-      MOZ_ASSERT(false, "Shouldn't be called after shutdown!");
-      return nullptr;
-    }
-
     // TODO: We cannot simply change this to RefPtr<FileInfo>, because
-    // FileInfo::AddRef also acquires the IndexedDatabaseManager::FileMutex.
+    // FileInfo::AddRef also acquires the FileManager::Mutex.
     // This looks quirky at least.
     FileInfo* fileInfo;
     {
-      AutoLock lock(IndexedDatabaseManager::FileMutex());
+      AutoLock lock(FileManager::Mutex());
       fileInfo = mFileInfos.Get(aId);
     }
 
@@ -46,18 +41,17 @@ class FileManagerBase {
   }
 
   MOZ_MUST_USE RefPtr<FileInfo> CreateFileInfo() {
-    MOZ_ASSERT(!IndexedDatabaseManager::IsClosed());
-
     // TODO: We cannot simply change this to RefPtr<FileInfo>, because
-    // FileInfo::AddRef also acquires the IndexedDatabaseManager::FileMutex.
+    // FileInfo::AddRef also acquires the FileManager::Mutex.
     // This looks quirky at least.
     FileInfo* fileInfo;
     {
-      AutoLock lock(IndexedDatabaseManager::FileMutex());
+      AutoLock lock(FileManager::Mutex());
 
       const int64_t id = ++mLastFileId;
 
-      fileInfo = new FileInfo(static_cast<FileManager*>(this), id);
+      fileInfo =
+          new FileInfo(FileManagerGuard{}, static_cast<FileManager*>(this), id);
 
       mFileInfos.Put(id, fileInfo);
     }
@@ -65,20 +59,15 @@ class FileManagerBase {
     return fileInfo;
   }
 
-  void RemoveFileInfo(const int64_t aId, const AutoLock& aFilesMutexLock) {
+  void RemoveFileInfo(const int64_t aId, const AutoLock& aFileMutexLock) {
 #ifdef DEBUG
-    aFilesMutexLock.AssertOwns(IndexedDatabaseManager::FileMutex());
+    aFileMutexLock.AssertOwns(FileManager::Mutex());
 #endif
     mFileInfos.Remove(aId);
   }
 
   nsresult Invalidate() {
-    if (IndexedDatabaseManager::IsClosed()) {
-      MOZ_ASSERT(false, "Shouldn't be called after shutdown!");
-      return NS_ERROR_UNEXPECTED;
-    }
-
-    AutoLock lock(IndexedDatabaseManager::FileMutex());
+    AutoLock lock(FileManager::Mutex());
 
     mInvalidated.Flip();
 
@@ -86,7 +75,7 @@ class FileManagerBase {
       FileInfo* info = iter.Data();
       MOZ_ASSERT(info);
 
-      return !info->LockedClearDBRefs();
+      return !info->LockedClearDBRefs(FileManagerGuard{});
     });
 
     return NS_OK;
@@ -102,7 +91,7 @@ class FileManagerBase {
   ~FileManagerBase() = default;
 
   // Access to the following fields must be protected by
-  // IndexedDatabaseManager::FileMutex()
+  // FileManager::Mutex()
   int64_t mLastFileId = 0;
   nsDataHashtable<nsUint64HashKey, FileInfo*> mFileInfos;
 

dom/indexedDB/IDBDatabase.cpp

@@ -6,7 +6,6 @@
 
 #include "IDBDatabase.h"
 
-#include "FileInfo.h"
 #include "IDBEvents.h"
 #include "IDBFactory.h"
 #include "IDBIndex.h"

dom/indexedDB/IDBIndex.cpp

@@ -6,7 +6,6 @@
 
 #include "IDBIndex.h"
 
-#include "FileInfo.h"
 #include "IDBCursorType.h"
 #include "IDBEvents.h"
 #include "IDBKeyRange.h"

dom/indexedDB/IDBMutableFile.cpp

@@ -7,7 +7,6 @@
 #include "IDBMutableFile.h"
 
 #include "ActorsChild.h"
-#include "FileInfo.h"
 #include "IDBDatabase.h"
 #include "IDBFactory.h"
 #include "IDBFileHandle.h"

dom/indexedDB/IDBObjectStore.cpp

@@ -9,7 +9,6 @@
 #include <numeric>
 #include <utility>
 
-#include "FileInfo.h"
 #include "IDBCursorType.h"
 #include "IDBDatabase.h"
 #include "IDBEvents.h"

dom/indexedDB/IndexedDatabase.h

@@ -12,6 +12,7 @@
 #include "nsCOMPtr.h"
 #include "nsTArray.h"
 #include "InitializedOnce.h"
+#include "FileInfoFwd.h"
 
 namespace mozilla {
 namespace dom {
@@ -22,7 +23,6 @@ class IDBMutableFile;
 
 namespace indexedDB {
 
-class FileInfo;
 class SerializedStructuredCloneReadInfo;
 
 struct StructuredCloneFile {

dom/indexedDB/IndexedDatabaseInlines.h

@@ -11,7 +11,6 @@
 #  error Must include IndexedDatabase.h first
 #endif
 
-#include "FileInfo.h"
 #include "FileManager.h"
 #include "IDBMutableFile.h"
 #include "mozilla/dom/indexedDB/PBackgroundIDBSharedTypes.h"

dom/indexedDB/IndexedDatabaseManager.cpp

@@ -215,9 +215,7 @@ auto DatabaseNameMatchPredicate(const nsAString* const aName) {
 
 }  // namespace
 
-IndexedDatabaseManager::IndexedDatabaseManager()
-    : mFileMutex("IndexedDatabaseManager.mFileMutex"),
-      mBackgroundActor(nullptr) {
+IndexedDatabaseManager::IndexedDatabaseManager() : mBackgroundActor(nullptr) {
   NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
 }
 

dom/indexedDB/IndexedDatabaseManager.h

@@ -132,13 +132,6 @@ class IndexedDatabaseManager final {
 
   static const nsCString& GetLocale();
 
-  static mozilla::Mutex& FileMutex() {
-    IndexedDatabaseManager* mgr = Get();
-    NS_ASSERTION(mgr, "Must have a manager here!");
-
-    return mgr->mFileMutex;
-  }
-
   static nsresult CommonPostHandleEvent(EventChainPostVisitor& aVisitor,
                                         IDBFactory* aFactory);
 
@@ -164,11 +157,6 @@ class IndexedDatabaseManager final {
   nsClassHashtable<nsRefPtrHashKey<FileManager>, nsTArray<int64_t>>
       mPendingDeleteInfos;
 
-  // Lock protecting FileManager.mFileInfos.
-  // It's s also used to atomically update FileInfo.mRefCnt, FileInfo.mDBRefCnt
-  // and FileInfo.mSliceRefCnt
-  mozilla::Mutex mFileMutex;
-
   nsCString mLocale;
 
   indexedDB::BackgroundUtilsChild* mBackgroundActor;

dom/indexedDB/moz.build

@@ -24,6 +24,7 @@ XPCSHELL_TESTS_MANIFESTS += [
 TEST_DIRS += ['test/gtest']
 
 EXPORTS.mozilla.dom += [
+    'FileInfoFwd.h',
     'FlippedOnce.h',
     'IDBCursor.h',
     'IDBCursorType.h',