Restructure contents of blimp/client.

blimp/client/feature/navigation_feature.h

Index: blimp/client/feature/navigation_feature.h
diff --git a/blimp/client/session/navigation_feature.h b/blimp/client/feature/navigation_feature.h
similarity index 92%
rename from blimp/client/session/navigation_feature.h
rename to blimp/client/feature/navigation_feature.h
index 5aa5c4a9e57fe7b6b320c5b23ba14b0efbdd8fac..ac5f555824308c01b4d8b67b13e4b3d193293e66 100644
--- a/blimp/client/session/navigation_feature.h
+++ b/blimp/client/feature/navigation_feature.h
@@ -2,8 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef BLIMP_CLIENT_SESSION_NAVIGATION_FEATURE_H_
-#define BLIMP_CLIENT_SESSION_NAVIGATION_FEATURE_H_
+#ifndef BLIMP_CLIENT_FEATURE_NAVIGATION_FEATURE_H_
+#define BLIMP_CLIENT_FEATURE_NAVIGATION_FEATURE_H_
+
+#include <map>
+#include <string>
 
 #include "base/containers/small_map.h"
 #include "base/macros.h"
@@ -69,4 +72,4 @@ class BLIMP_CLIENT_EXPORT NavigationFeature : public BlimpMessageProcessor {
 }  // namespace client
 }  // namespace blimp
 
-#endif  // BLIMP_CLIENT_SESSION_NAVIGATION_FEATURE_H_
+#endif  // BLIMP_CLIENT_FEATURE_NAVIGATION_FEATURE_H_