[Sync] Replacing NULL with nullptr in code and null in comments for components/sync/

components/sync/syncable/write_node.cc

 // Copyright (c) 2012 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/syncable/write_node.h"
 
 #include <memory>
 
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 177 matching lines @@
   entity_specifics.mutable_typed_url()->CopyFrom(new_value);
   SetEntitySpecifics(entity_specifics);
 }
 
 void WriteNode::SetExternalId(int64_t id) {
   if (GetExternalId() != id)
     entry_->PutLocalExternalId(id);
 }
 
 WriteNode::WriteNode(WriteTransaction* transaction)
-    : entry_(NULL), transaction_(transaction) {
+    : entry_(nullptr), transaction_(transaction) {
   DCHECK(transaction);
 }
 
 WriteNode::~WriteNode() {
   delete entry_;
 }
 
 // Find an existing node matching the ID |id|, and bind this WriteNode to it.
 // Return true on success.
 BaseNode::InitByLookupResult WriteNode::InitByIdLookup(int64_t id) {
@@ skipping 42 matching lines @@
   ModelType model_type = GetModelType();
   DCHECK_EQ(model_type, NIGORI);
   return INIT_OK;
 }
 
 // Create a new node with default properties, and bind this WriteNode to it.
 // Return true on success.
 bool WriteNode::InitBookmarkByCreation(const BaseNode& parent,
                                        const BaseNode* predecessor) {
   DCHECK(!entry_) << "Init called twice";
-  // |predecessor| must be a child of |parent| or NULL.
+  // |predecessor| must be a child of |parent| or null.
   if (predecessor && predecessor->GetParentId() != parent.GetId()) {
     DCHECK(false);
     return false;
   }
 
   syncable::Id parent_id = parent.GetSyncId();
   DCHECK(!parent_id.IsNull());
 
   // Start out with a dummy name.  We expect
   // the caller to set a meaningful name after creation.
@@ skipping 125 matching lines @@
   }
 
   // Mark this entry as unsynced, to wake up the syncer.
   MarkForSyncing();
 
   return INIT_SUCCESS;
 }
 
 bool WriteNode::SetPosition(const BaseNode& new_parent,
                             const BaseNode* predecessor) {
-  // |predecessor| must be a child of |new_parent| or NULL.
+  // |predecessor| must be a child of |new_parent| or null.
   if (predecessor && predecessor->GetParentId() != new_parent.GetId()) {
     DCHECK(false);
     return false;
   }
 
   syncable::Id new_parent_id = new_parent.GetSyncId();
   DCHECK(!new_parent_id.IsNull());
 
   // Filter out redundant changes if both the parent and the predecessor match.
   if (new_parent_id == entry_->GetParentId()) {
@@ skipping 51 matching lines @@
   syncable::Id predecessor_id =
       predecessor ? predecessor->GetSyncId() : syncable::Id();
   return entry_->PutPredecessor(predecessor_id);
 }
 
 void WriteNode::MarkForSyncing() {
   syncable::MarkForSyncing(entry_);
 }
 
 }  // namespace syncer