Rename shell namespace to service_manager

mash/quick_launch/main.cc

Index: mash/quick_launch/main.cc
diff --git a/mash/quick_launch/main.cc b/mash/quick_launch/main.cc
index 35a74f264ae44ea48f5adc360b24f83f3cefd3be..2b9b3703ce3412aa0b21d234e1f2da1409c944b9 100644
--- a/mash/quick_launch/main.cc
+++ b/mash/quick_launch/main.cc
@@ -7,6 +7,6 @@
 #include "services/service_manager/public/cpp/service_runner.h"
 
 MojoResult ServiceMain(MojoHandle service_request_handle) {
-  shell::ServiceRunner runner(new mash::quick_launch::QuickLaunch);
+  service_manager::ServiceRunner runner(new mash::quick_launch::QuickLaunch);
   return runner.Run(service_request_handle);
 }