Revert "Remove legacy poller"

This reverts commit d88e15cee750cd647a900098d82f87cc25aa8dbe.
diff --git a/tools/run_tests/sources_and_headers.json b/tools/run_tests/sources_and_headers.json
index 24d23fe..fe67426 100644
--- a/tools/run_tests/sources_and_headers.json
+++ b/tools/run_tests/sources_and_headers.json
@@ -5530,6 +5530,7 @@
       "src/core/lib/iomgr/closure.h", 
       "src/core/lib/iomgr/endpoint.h", 
       "src/core/lib/iomgr/endpoint_pair.h", 
+      "src/core/lib/iomgr/ev_poll_and_epoll_posix.h", 
       "src/core/lib/iomgr/ev_poll_posix.h", 
       "src/core/lib/iomgr/ev_posix.h", 
       "src/core/lib/iomgr/exec_ctx.h", 
@@ -5629,6 +5630,8 @@
       "src/core/lib/iomgr/endpoint_pair.h", 
       "src/core/lib/iomgr/endpoint_pair_posix.c", 
       "src/core/lib/iomgr/endpoint_pair_windows.c", 
+      "src/core/lib/iomgr/ev_poll_and_epoll_posix.c", 
+      "src/core/lib/iomgr/ev_poll_and_epoll_posix.h", 
       "src/core/lib/iomgr/ev_poll_posix.c", 
       "src/core/lib/iomgr/ev_poll_posix.h", 
       "src/core/lib/iomgr/ev_posix.c",