[Blimp client] Move client code into blimp::client namespace

blimp/client/session/blimp_client_session.cc

Index: blimp/client/session/blimp_client_session.cc
diff --git a/blimp/client/session/blimp_client_session.cc b/blimp/client/session/blimp_client_session.cc
index 2df28d7e4ca40b365a874d3ec5cc39d9138bdfcf..b6af2e5016e9a47ced95c1edfbbec48d6facb366 100644
--- a/blimp/client/session/blimp_client_session.cc
+++ b/blimp/client/session/blimp_client_session.cc
@@ -17,6 +17,7 @@
 #include "blimp/net/tcp_client_transport.h"
 
 namespace blimp {
+namespace client {
 namespace {
 
 // TODO(kmarshall): Take values from configuration data.
@@ -182,4 +183,5 @@ RenderWidgetFeature* BlimpClientSession::GetRenderWidgetFeature() const {
   return render_widget_feature_.get();
 }
 
+}  // namespace client
 }  // namespace blimp