[WIP][tracing] Add memory dump provider for sync Directory

components/sync_driver/glue/sync_backend_host_core.cc

 // Copyright 2013 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 "components/sync_driver/glue/sync_backend_host_core.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/files/file_util.h"
 #include "base/location.h"
 #include "base/single_thread_task_runner.h"
+#include "base/trace_event/memory_dump_manager.h"
 #include "components/data_use_measurement/core/data_use_user_data.h"
 #include "components/invalidation/public/invalidation_util.h"
 #include "components/invalidation/public/object_id_invalidation_map.h"
 #include "components/sync_driver/glue/sync_backend_registrar.h"
 #include "components/sync_driver/invalidation_adapter.h"
 #include "components/sync_driver/local_device_info_provider_impl.h"
 #include "sync/internal_api/public/events/protocol_event.h"
 #include "sync/internal_api/public/http_post_provider_factory.h"
 #include "sync/internal_api/public/internal_components_factory.h"
 #include "sync/internal_api/public/sessions/commit_counters.h"
@@ skipping 99 matching lines @@
       forward_protocol_events_(false),
       forward_type_info_(false),
       weak_ptr_factory_(this) {
   DCHECK(backend.get());
 }
 
 SyncBackendHostCore::~SyncBackendHostCore() {
   DCHECK(!sync_manager_.get());
 }
 
+bool SyncBackendHostCore::OnMemoryDump(
+    const base::trace_event::MemoryDumpArgs& args,
+    base::trace_event::ProcessMemoryDump* pmd) {
+  DCHECK_EQ(base::MessageLoop::current(), sync_loop_);
+  if (!sync_manager_)
+    return false;
+  sync_manager_->OnMemoryDump(pmd);
+  return true;
+}
+
 void SyncBackendHostCore::OnSyncCycleCompleted(
     const syncer::sessions::SyncSessionSnapshot& snapshot) {
   if (!sync_loop_)
     return;
   DCHECK(sync_loop_->task_runner()->BelongsToCurrentThread());
 
   host_.Call(
       FROM_HERE,
       &SyncBackendHostImpl::HandleSyncCycleCompletedOnFrontendLoop,
       snapshot);
@@ skipping 310 matching lines @@
       options->restored_keystore_key_for_bootstrapping;
   args.internal_components_factory =
       std::move(options->internal_components_factory);
   args.encryptor = &encryptor_;
   args.unrecoverable_error_handler = options->unrecoverable_error_handler;
   args.report_unrecoverable_error_function =
       options->report_unrecoverable_error_function;
   args.cancelation_signal = &stop_syncing_signal_;
   args.saved_nigori_state = std::move(options->saved_nigori_state);
   sync_manager_->Init(&args);
+  base::trace_event::MemoryDumpManager::GetInstance()->RegisterDumpProvider(
+      this, "SyncDirectory", sync_loop_->task_runner());
 }
 
 void SyncBackendHostCore::DoUpdateCredentials(
     const syncer::SyncCredentials& credentials) {
   DCHECK(sync_loop_->task_runner()->BelongsToCurrentThread());
   // UpdateCredentials can be called during backend initialization, possibly
   // when backend initialization has failed but hasn't notified the UI thread
   // yet. In that case, the sync manager may have been destroyed on the sync
   // thread before this task was executed, so we do nothing.
   if (sync_manager_) {
@@ skipping 96 matching lines @@
 
   if (reason == syncer::DISABLE_SYNC)
     DeleteSyncDataFolder();
 
   host_.Reset();
   weak_ptr_factory_.InvalidateWeakPtrs();
 }
 
 void SyncBackendHostCore::DoDestroySyncManager(syncer::ShutdownReason reason) {
   DCHECK(sync_loop_->task_runner()->BelongsToCurrentThread());
+
+  base::trace_event::MemoryDumpManager::GetInstance()->UnregisterDumpProvider(
+      this);
   if (sync_manager_) {
     DisableDirectoryTypeDebugInfoForwarding();
     save_changes_timer_.reset();
     sync_manager_->RemoveObserver(this);
     sync_manager_->ShutdownOnSyncThread(reason);
     sync_manager_.reset();
   }
 }
 
 void SyncBackendHostCore::DoConfigureSyncer(
@@ skipping 174 matching lines @@
 
 void SyncBackendHostCore::ClearServerDataDone(
     const base::Closure& frontend_callback) {
   DCHECK(sync_loop_->task_runner()->BelongsToCurrentThread());
   host_.Call(FROM_HERE, &SyncBackendHostImpl::ClearServerDataDoneOnFrontendLoop,
              frontend_callback);
 }
 
 
 }  // namespace browser_sync