Revert of Mandoline UI Process: Update namespaces and file names

components/mus/focus_controller.cc

Index: components/mus/focus_controller.cc
diff --git a/components/mus/focus_controller.cc b/components/mus/focus_controller.cc
index f2b56fc199066ebccc94a8d3e27eb39e93785163..af191126ed943e73fbee9915094710c1adb16d6e 100644
--- a/components/mus/focus_controller.cc
+++ b/components/mus/focus_controller.cc
@@ -8,7 +8,7 @@
 #include "components/mus/server_view.h"
 #include "components/mus/server_view_drawn_tracker.h"
 
-namespace mus {
+namespace view_manager {
 
 FocusController::FocusController(FocusControllerDelegate* delegate)
     : delegate_(delegate) {}
@@ -48,4 +48,4 @@
   SetFocusedViewImpl(ancestor, CHANGE_SOURCE_DRAWN_STATE_CHANGED);
 }
 
-}  // namespace mus
+}  // namespace view_manager