Revert of [Service Manager] Get rid of dynamic service discovery

ui/views/mus/run_all_unittests_mus.cc

Index: ui/views/mus/run_all_unittests_mus.cc
diff --git a/ui/views/mus/run_all_unittests_mus.cc b/ui/views/mus/run_all_unittests_mus.cc
index 49d9aaf837103c5c78bdcf65bb0f55e16a183f77..05e4f0c82a2770200a1878c6c3d1f62fe7206028 100644
--- a/ui/views/mus/run_all_unittests_mus.cc
+++ b/ui/views/mus/run_all_unittests_mus.cc
@@ -4,6 +4,6 @@
 
 #include "ui/views/mus/views_mus_test_suite.h"
 
-int main(int argc, char** argv) {
+int MasterProcessMain(int argc, char** argv) {
   return views::ViewsMusTestSuite(argc, argv).RunTests();
 }