sync: Add ControlPreference protobuf and supporting code

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 642037c631be7369fbbe2de2c9154daad7447c5e..e2267b6c0b0e88cb335dfa55f29734a093efac9d 100644
--- a/sync/protocol/proto_value_conversions_unittest.cc
+++ b/sync/protocol/proto_value_conversions_unittest.cc
@@ -16,6 +16,7 @@
 #include "sync/protocol/app_specifics.pb.h"
 #include "sync/protocol/autofill_specifics.pb.h"
 #include "sync/protocol/bookmark_specifics.pb.h"
+#include "sync/protocol/control_preference_specifics.pb.h"
 #include "sync/protocol/device_info_specifics.pb.h"
 #include "sync/protocol/encryption.pb.h"
 #include "sync/protocol/experiments_specifics.pb.h"
@@ -49,7 +50,7 @@ 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(20, MODEL_TYPE_COUNT);
+  EXPECT_EQ(21, 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
@@ -138,6 +139,10 @@ TEST_F(ProtoValueConversionsTest, BookmarkSpecificsData) {
   EXPECT_EQ(icon_url, encoded_icon_url);
 }
 
+TEST_F(ProtoValueConversionsTest, ControlPreferenceSpecificsToValue) {
+  TestSpecificsToValue(ControlPreferenceSpecificsToValue);
+}
+
 TEST_F(ProtoValueConversionsTest, DeviceInfoSpecificsToValue) {
   TestSpecificsToValue(DeviceInfoSpecificsToValue);
 }
@@ -200,6 +205,7 @@ TEST_F(ProtoValueConversionsTest, EntitySpecificsToValue) {
   SET_FIELD(autofill);
   SET_FIELD(autofill_profile);
   SET_FIELD(bookmark);
+  SET_FIELD(control_preference);
   SET_FIELD(experiments);
   SET_FIELD(extension);
   SET_FIELD(extension_setting);