Add blimp to root GN check_targets

blimp/client/feature/navigation_feature.h

Index: blimp/client/feature/navigation_feature.h
diff --git a/blimp/client/feature/navigation_feature.h b/blimp/client/feature/navigation_feature.h
index b971bb70988279c47749ac0a9204db0b510bc0ac..224764cd87beca74b6359ab23cfa442d20b8bfd0 100644
--- a/blimp/client/feature/navigation_feature.h
+++ b/blimp/client/feature/navigation_feature.h
@@ -10,7 +10,6 @@
 
 #include "base/containers/small_map.h"
 #include "base/macros.h"
-#include "blimp/client/blimp_client_export.h"
 #include "blimp/net/blimp_message_processor.h"
 
 class GURL;
@@ -22,7 +21,7 @@ namespace client {
 // Handles all incoming and outgoing protobuf messages of type
 // RenderWidget::NAVIGATION.  Delegates can be added to be notified of incoming
 // messages.
-class BLIMP_CLIENT_EXPORT NavigationFeature : public BlimpMessageProcessor {
+class NavigationFeature : public BlimpMessageProcessor {
  public:
   // A delegate to be notified of specific navigation events related to a
   // a particular tab.