[Sync] Replace uses of ObserverListThreadSafe with WeakHandles

chrome/browser/sync/syncable/syncable.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/sync/syncable/syncable.h"
 
 #include <algorithm>
 #include <cstring>
 #include <functional>
 #include <iomanip>
@@ skipping 331 matching lines @@
   SetFieldValues(*this, kernel_info,
                  &GetBitTempString, &Value::CreateBooleanValue,
                  BIT_TEMPS_BEGIN, BIT_TEMPS_END - 1);
 
   return kernel_info;
 }
 
 ///////////////////////////////////////////////////////////////////////////
 // Directory
 
-void Directory::InitKernel(const std::string& name,
-                           DirectoryChangeDelegate* delegate) {
-  DCHECK(kernel_ == NULL);
-  kernel_ = new Kernel(FilePath(), name, KernelLoadInfo(), delegate);
+void Directory::InitKernelForTest(
+    const std::string& name,
+    DirectoryChangeDelegate* delegate,
+    const browser_sync::WeakHandle<TransactionObserver>&
+        transaction_observer) {
+  DCHECK(!kernel_);
+  kernel_ =  new Kernel(FilePath(), name, KernelLoadInfo(),
+                        delegate, transaction_observer);
 }
 
 Directory::PersistedKernelInfo::PersistedKernelInfo()
     : next_id(0) {
   for (int i = FIRST_REAL_MODEL_TYPE; i < MODEL_TYPE_COUNT; ++i) {
     reset_download_progress(ModelTypeFromInt(i));
   }
 }
 
 Directory::PersistedKernelInfo::~PersistedKernelInfo() {}
 
 void Directory::PersistedKernelInfo::reset_download_progress(
     ModelType model_type) {
   download_progress[model_type].set_data_type_id(
       GetExtensionFieldNumberFromModelType(model_type));
   // An empty-string token indicates no prior knowledge.
   download_progress[model_type].set_token(std::string());
 }
 
 Directory::SaveChangesSnapshot::SaveChangesSnapshot()
     : kernel_info_status(KERNEL_SHARE_INFO_INVALID) {
 }
 
 Directory::SaveChangesSnapshot::~SaveChangesSnapshot() {}
 
-Directory::Kernel::Kernel(const FilePath& db_path,
-                          const string& name,
-                          const KernelLoadInfo& info,
-                          DirectoryChangeDelegate* delegate)
+Directory::Kernel::Kernel(
+    const FilePath& db_path, const string& name,
+    const KernelLoadInfo& info, DirectoryChangeDelegate* delegate,
+    const browser_sync::WeakHandle<TransactionObserver>&
+        transaction_observer)
     : db_path(db_path),
       refcount(1),
       next_write_transaction_id(0),
       name(name),
       metahandles_index(new Directory::MetahandlesIndex),
       ids_index(new Directory::IdsIndex),
       parent_id_child_index(new Directory::ParentIdChildIndex),
       client_tag_index(new Directory::ClientTagIndex),
       unapplied_update_metahandles(new MetahandleSet),
       unsynced_metahandles(new MetahandleSet),
       dirty_metahandles(new MetahandleSet),
       metahandles_to_purge(new MetahandleSet),
       info_status(Directory::KERNEL_SHARE_INFO_VALID),
       persisted_info(info.kernel_info),
       cache_guid(info.cache_guid),
       next_metahandle(info.max_metahandle + 1),
       delegate(delegate),
-      observers(new ObserverListThreadSafe<TransactionObserver>()) {
+      transaction_observer(transaction_observer) {
   DCHECK(delegate);
+  DCHECK(transaction_observer.IsInitialized());
 }
 
 void Directory::Kernel::AddRef() {
   base::subtle::NoBarrier_AtomicIncrement(&refcount, 1);
 }
 
 void Directory::Kernel::Release() {
   if (!base::subtle::NoBarrier_AtomicIncrement(&refcount, -1))
     delete this;
 }
@@ skipping 11 matching lines @@
   delete metahandles_index;
 }
 
 Directory::Directory() : kernel_(NULL), store_(NULL) {
 }
 
 Directory::~Directory() {
   Close();
 }
 
-DirOpenResult Directory::Open(const FilePath& file_path, const string& name,
-                              DirectoryChangeDelegate* delegate) {
-  const DirOpenResult result = OpenImpl(file_path, name, delegate);
+DirOpenResult Directory::Open(
+    const FilePath& file_path, const string& name,
+    DirectoryChangeDelegate* delegate,
+    const browser_sync::WeakHandle<TransactionObserver>&
+        transaction_observer) {
+  const DirOpenResult result =
+      OpenImpl(file_path, name, delegate, transaction_observer);
   if (OPENED != result)
     Close();
   return result;
 }
 
 void Directory::InitializeIndices() {
   MetahandlesIndex::iterator it = kernel_->metahandles_index->begin();
   for (; it != kernel_->metahandles_index->end(); ++it) {
     EntryKernel* entry = *it;
     InitializeIndexEntry<ParentIdAndHandleIndexer>(entry,
         kernel_->parent_id_child_index);
     InitializeIndexEntry<IdIndexer>(entry, kernel_->ids_index);
     InitializeIndexEntry<ClientTagIndexer>(entry, kernel_->client_tag_index);
     if (entry->ref(IS_UNSYNCED))
       kernel_->unsynced_metahandles->insert(entry->ref(META_HANDLE));
     if (entry->ref(IS_UNAPPLIED_UPDATE))
       kernel_->unapplied_update_metahandles->insert(entry->ref(META_HANDLE));
     DCHECK(!entry->is_dirty());
   }
 }
 
 DirectoryBackingStore* Directory::CreateBackingStore(
     const string& dir_name, const FilePath& backing_filepath) {
   return new DirectoryBackingStore(dir_name, backing_filepath);
 }
 
-DirOpenResult Directory::OpenImpl(const FilePath& file_path,
-                                  const string& name,
-                                  DirectoryChangeDelegate* delegate) {
+DirOpenResult Directory::OpenImpl(
+    const FilePath& file_path,
+    const string& name,
+    DirectoryChangeDelegate* delegate,
+    const browser_sync::WeakHandle<TransactionObserver>&
+        transaction_observer) {
   DCHECK_EQ(static_cast<DirectoryBackingStore*>(NULL), store_);
   FilePath db_path(file_path);
   file_util::AbsolutePath(&db_path);
   store_ = CreateBackingStore(name, db_path);
 
   KernelLoadInfo info;
   // Temporary indices before kernel_ initialized in case Load fails. We 0(1)
   // swap these later.
   MetahandlesIndex metas_bucket;
   DirOpenResult result = store_->Load(&metas_bucket, &info);
   if (OPENED != result)
     return result;
 
-  kernel_ = new Kernel(db_path, name, info, delegate);
+  kernel_ = new Kernel(db_path, name, info, delegate, transaction_observer);
   kernel_->metahandles_index->swap(metas_bucket);
   InitializeIndices();
   return OPENED;
 }
 
 void Directory::Close() {
   if (store_)
     delete store_;
   store_ = NULL;
   if (kernel_) {
@@ skipping 611 matching lines @@
     int64 elapsed_ms = check_timer.Elapsed().InMilliseconds();
     if (elapsed_ms > max_ms) {
       VLOG(1) << "Cutting Invariant check short after " << elapsed_ms
               << "ms. Processed " << entries_done << "/" << handles.size()
               << " entries";
       return;
     }
   }
 }
 
-void Directory::AddTransactionObserver(TransactionObserver* observer) {
-  kernel_->observers->AddObserver(observer);
-}
-
-void Directory::RemoveTransactionObserver(TransactionObserver* observer) {
-  kernel_->observers->RemoveObserver(observer);
-}
-
 ///////////////////////////////////////////////////////////////////////////////
 // ScopedKernelLock
 
 ScopedKernelLock::ScopedKernelLock(const Directory* dir)
   :  scoped_lock_(dir->kernel_->mutex), dir_(const_cast<Directory*>(dir)) {
 }
 
 ///////////////////////////////////////////////////////////////////////////
 // Transactions
 
@@ skipping 16 matching lines @@
         << name_ << " transaction completed in " << elapsed.InSecondsF()
         << " seconds.";
 }
 
 BaseTransaction::BaseTransaction(const tracked_objects::Location& from_here,
                                  const char* name,
                                  WriterTag writer,
                                  Directory* directory)
     : from_here_(from_here), name_(name), writer_(writer),
       directory_(directory), dirkernel_(directory->kernel_) {
-  dirkernel_->observers->Notify(
+  dirkernel_->transaction_observer.Call(FROM_HERE,
       &TransactionObserver::OnTransactionStart, from_here_, writer_);
 }
 
 BaseTransaction::~BaseTransaction() {
   if (writer_ != INVALID) {
-    dirkernel_->observers->Notify(
+    dirkernel_->transaction_observer.Call(FROM_HERE,
         &TransactionObserver::OnTransactionEnd, from_here_, writer_);
   }
 }
 
 ReadTransaction::ReadTransaction(const tracked_objects::Location& location,
                                  Directory* directory)
     : BaseTransaction(location, "Read", INVALID, directory) {
   Lock();
 }
 
@@ skipping 88 matching lines @@
         immutable_write_transaction_info, this);
   } else {
     delegate->HandleCalculateChangesChangeEventFromSyncer(
         immutable_write_transaction_info, this);
   }
 
   ModelTypeBitSet models_with_changes =
       delegate->HandleTransactionEndingChangeEvent(
           immutable_write_transaction_info, this);
 
-  dirkernel_->observers->Notify(
+  dirkernel_->transaction_observer.Call(FROM_HERE,
       &TransactionObserver::OnTransactionWrite,
       immutable_write_transaction_info, models_with_changes);
 
   return models_with_changes;
 }
 
 void WriteTransaction::NotifyTransactionComplete(
     ModelTypeBitSet models_with_changes) {
   dirkernel_->delegate->HandleTransactionCompleteChangeEvent(
       models_with_changes);
@@ skipping 739 matching lines @@
     if (entry->ref(NEXT_ID).IsRoot() ||
         entry->ref(NEXT_ID) != entry->ref(PREV_ID)) {
       return entry;
     }
   }
   // There were no children in the linked list.
   return NULL;
 }
 
 }  // namespace syncable