Put most of netd into the android::net namespace.

Test: netd_{unit,integration}_test pass
Test: bullhead builds, boots
Bug: 34873832
Change-Id: I0a252328041b342f9c03cd08c11a69d452b045b3
diff --git a/server/NetworkController.cpp b/server/NetworkController.cpp
index c891391..8e4c69d 100644
--- a/server/NetworkController.cpp
+++ b/server/NetworkController.cpp
@@ -47,6 +47,9 @@
 #include "RouteController.h"
 #include "VirtualNetwork.h"
 
+namespace android {
+namespace net {
+
 namespace {
 
 // Keep these in sync with ConnectivityService.java.
@@ -666,3 +669,6 @@
     }
     return 0;
 }
+
+}  // namespace net
+}  // namespace android