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

blimp/client/session/blimp_client_session_android.h

Index: blimp/client/session/blimp_client_session_android.h
diff --git a/blimp/client/session/blimp_client_session_android.h b/blimp/client/session/blimp_client_session_android.h
index e752f0b14bdb1d4e7dd0971318915814ad645e79..0e0497ca89165eac0a7faa1df469a32893329d7d 100644
--- a/blimp/client/session/blimp_client_session_android.h
+++ b/blimp/client/session/blimp_client_session_android.h
@@ -10,6 +10,7 @@
 #include "blimp/client/session/blimp_client_session.h"
 
 namespace blimp {
+namespace client {
 
 class BlimpClientSessionAndroid : public BlimpClientSession {
  public:
@@ -31,6 +32,7 @@ class BlimpClientSessionAndroid : public BlimpClientSession {
   DISALLOW_COPY_AND_ASSIGN(BlimpClientSessionAndroid);
 };
 
+}  // namespace client
 }  // namespace blimp
 
 #endif  // BLIMP_CLIENT_SESSION_BLIMP_CLIENT_SESSION_ANDROID_H_