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

blimp/client/session/navigation_feature.h

Index: blimp/client/session/navigation_feature.h
diff --git a/blimp/client/session/navigation_feature.h b/blimp/client/session/navigation_feature.h
index 91b4ecb3f6b7d84e856515dc7e2af3ab5ec6bcb2..5aa5c4a9e57fe7b6b320c5b23ba14b0efbdd8fac 100644
--- a/blimp/client/session/navigation_feature.h
+++ b/blimp/client/session/navigation_feature.h
@@ -14,6 +14,7 @@ class GURL;
 class SkBitmap;
 
 namespace blimp {
+namespace client {
 
 // Handles all incoming and outgoing protobuf messages of type
 // RenderWidget::NAVIGATION.  Delegates can be added to be notified of incoming
@@ -65,6 +66,7 @@ class BLIMP_CLIENT_EXPORT NavigationFeature : public BlimpMessageProcessor {
   DISALLOW_COPY_AND_ASSIGN(NavigationFeature);
 };
 
+}  // namespace client
 }  // namespace blimp
 
 #endif  // BLIMP_CLIENT_SESSION_NAVIGATION_FEATURE_H_