[Sync] Add history delete directive type

sync/protocol/proto_value_conversions_unittest.cc

Index: sync/protocol/proto_value_conversions_unittest.cc
diff --git a/sync/protocol/proto_value_conversions_unittest.cc b/sync/protocol/proto_value_conversions_unittest.cc
index fd364501d144a89b61ccbc11c0f60c179dd71cbf..f9a88200f6aef3858c04f2b8f5d6fc9e8cae33ea 100644
--- a/sync/protocol/proto_value_conversions_unittest.cc
+++ b/sync/protocol/proto_value_conversions_unittest.cc
@@ -47,7 +47,7 @@ TEST_F(ProtoValueConversionsTest, ProtoChangeCheck) {
   // If this number changes, that means we added or removed a data
   // type.  Don't forget to add a unit test for {New
   // type}SpecificsToValue below.
-  EXPECT_EQ(17, MODEL_TYPE_COUNT);
+  EXPECT_EQ(18, MODEL_TYPE_COUNT);
 
   // We'd also like to check if we changed any field in our messages.
   // However, that's hard to do: sizeof could work, but it's
@@ -128,6 +128,10 @@ TEST_F(ProtoValueConversionsTest, ExtensionSpecificsToValue) {
   TestSpecificsToValue(ExtensionSpecificsToValue);
 }
 
+TEST_F(ProtoValueConversionsTest, HistoryDeleteDirectiveSpecificsToValue) {
+  TestSpecificsToValue(HistoryDeleteDirectiveSpecificsToValue);
+}
+
 TEST_F(ProtoValueConversionsTest, NigoriSpecificsToValue) {
   TestSpecificsToValue(NigoriSpecificsToValue);
 }
@@ -172,6 +176,7 @@ TEST_F(ProtoValueConversionsTest, EntitySpecificsToValue) {
   SET_FIELD(bookmark);
   SET_FIELD(extension);
   SET_FIELD(extension_setting);
+  SET_FIELD(history_delete_directive);
   SET_FIELD(nigori);
   SET_FIELD(password);
   SET_FIELD(preference);