Add merge rules for first read time

components/reading_list/ios/reading_list_store.h

Index: components/reading_list/ios/reading_list_store.h
diff --git a/components/reading_list/ios/reading_list_store.h b/components/reading_list/ios/reading_list_store.h
index 4dd3cfe88bc71469738958370b52dfa4afb5b842..e032daf03d276b646c753289c58ee67a2605a505 100644
--- a/components/reading_list/ios/reading_list_store.h
+++ b/components/reading_list/ios/reading_list_store.h
@@ -80,6 +80,10 @@ class ReadingListStore : public syncer::ModelTypeSyncBridge,
   // - URL must be the same.
   // - title must verify rhs.title.compare(lhs.title) >= 0
   // - rhs.creation_time_us >= lhs.creation_time_us
+  // - if rhs.creation_time_us > lhs.creation_time_us, rhs.first_read_time_us
+  //          can be anything.
+  // - if rhs.creation_time_us == lhs.creation_time_us, t

[gambard, 2016/12/09 08:06:55]

remove "t"

+  //          rhs.first_read_time_us <= lhs.first_read_time_us

[gambard, 2016/12/09 08:06:55]

What happens if lhs.first_read_time_us == 0?

   // - rhs.update_time_us >= lhs.update_time_us
   // - if rhs.update_time_us > lhs.update_time_us, rhs.state can be anything.
   // - if rhs.update_time_us == lhs.update_time_us, rhs.state >= lhs.state in