Add EventFilter encoding (#11178)

diff --git a/src/app/BUILD.gn b/src/app/BUILD.gn
index 27a1809..cc55642 100644
--- a/src/app/BUILD.gn
+++ b/src/app/BUILD.gn
@@ -65,6 +65,8 @@
     "MessageDef/CommandPathIB.h",
     "MessageDef/EventDataElement.cpp",
     "MessageDef/EventDataElement.h",
+    "MessageDef/EventFilterIB.cpp",
+    "MessageDef/EventFilters.cpp",
     "MessageDef/EventList.cpp",
     "MessageDef/EventList.h",
     "MessageDef/EventPath.cpp",