Split event notification out of ev_epoll_linux.c
diff --git a/tools/doxygen/Doxyfile.c++.internal b/tools/doxygen/Doxyfile.c++.internal
index 209d544..afab2296 100644
--- a/tools/doxygen/Doxyfile.c++.internal
+++ b/tools/doxygen/Doxyfile.c++.internal
@@ -971,6 +971,8 @@
src/core/lib/iomgr/iomgr_windows.c \
src/core/lib/iomgr/load_file.c \
src/core/lib/iomgr/load_file.h \
+src/core/lib/iomgr/lockfree_event.c \
+src/core/lib/iomgr/lockfree_event.h \
src/core/lib/iomgr/network_status_tracker.c \
src/core/lib/iomgr/network_status_tracker.h \
src/core/lib/iomgr/polling_entity.c \