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

components/sync/syncable/entry_kernel.h

 // Copyright 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.
 
 #ifndef COMPONENTS_SYNC_SYNCABLE_ENTRY_KERNEL_H_
 #define COMPONENTS_SYNC_SYNCABLE_ENTRY_KERNEL_H_
 
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 122 matching lines @@
   UNIQUE_BOOKMARK_TAG,  // Client tags for bookmark items
   STRING_FIELDS_END,
 };
 
 enum {
   STRING_FIELDS_COUNT = STRING_FIELDS_END - STRING_FIELDS_BEGIN,
   PROTO_FIELDS_BEGIN = STRING_FIELDS_END
 };
 
 // From looking at the sqlite3 docs, it's not directly stated, but it
-// seems the overhead for storing a NULL blob is very small.
+// seems the overhead for storing a null blob is very small.
 enum ProtoField {
   SPECIFICS = PROTO_FIELDS_BEGIN,
   SERVER_SPECIFICS,
   BASE_SERVER_SPECIFICS,
   PROTO_FIELDS_END,
 };
 
 enum {
   PROTO_FIELDS_COUNT = PROTO_FIELDS_END - PROTO_FIELDS_BEGIN,
   UNIQUE_POSITION_FIELDS_BEGIN = PROTO_FIELDS_END
@@ skipping 212 matching lines @@
   }
 
   ModelType GetModelType() const;
   ModelType GetServerModelType() const;
   bool ShouldMaintainPosition() const;
   bool ShouldMaintainHierarchy() const;
 
   // Dumps all kernel info into a DictionaryValue and returns it.
   // Transfers ownership of the DictionaryValue to the caller.
   // Note: |cryptographer| is an optional parameter for use in decrypting
-  // encrypted specifics. If it is NULL or the specifics are not decryptsble,
+  // encrypted specifics. If it is null or the specifics are not decryptsble,
   // they will be serialized as empty proto's.
   base::DictionaryValue* ToValue(Cryptographer* cryptographer) const;
 
  private:
   // Tracks whether this entry needs to be saved to the database.
   bool dirty_;
 };
 
 template <typename T>
 class EntryKernelLessByMetaHandle {
@@ skipping 25 matching lines @@
 
 std::unique_ptr<base::ListValue> EntryKernelMutationMapToValue(
     const EntryKernelMutationMap& mutations);
 
 std::ostream& operator<<(std::ostream& os, const EntryKernel& entry_kernel);
 
 }  // namespace syncable
 }  // namespace syncer
 
 #endif  // COMPONENTS_SYNC_SYNCABLE_ENTRY_KERNEL_H_