Add framework for sending feedback for Blimp.

blimp/client/core/blimp_client_context_impl.h

Index: blimp/client/core/blimp_client_context_impl.h
diff --git a/blimp/client/core/blimp_client_context_impl.h b/blimp/client/core/blimp_client_context_impl.h
index 8ee0f2a3027965c1e8dcc8724f157c20b086b2cd..dee8bd6a5161c34337de1b95c8ad99f55f4c5ed0 100644
--- a/blimp/client/core/blimp_client_context_impl.h
+++ b/blimp/client/core/blimp_client_context_impl.h
@@ -7,6 +7,7 @@
 
 #include <memory>
 #include <string>
+#include <unordered_map>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ -62,6 +63,9 @@ class BlimpClientContextImpl
   void Connect() override;
   void ConnectWithAssignment(const Assignment& assignment) override;
 
+  // Creates a data object containing data about Blimp to be used for feedback.
+  std::unordered_map<std::string, std::string> CreateFeedbackData();
+
  protected:
   // Returns the URL to use for connections to the assigner. Used to construct
   // the AssignmentSource.