[BattOr] Retry battor_agent commands when they fail.

tools/battor_agent/battor_agent.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef TOOLS_BATTOR_AGENT_BATTOR_AGENT_H_
 #define TOOLS_BATTOR_AGENT_BATTOR_AGENT_H_
 
 #include <map>
 
 #include "base/cancelable_callback.h"
@@ skipping 108 matching lines @@
     // Actions required for returning firmware git hash.
     SEND_GIT_HASH_REQUEST,
     READ_GIT_HASH,
   };
 
   // Performs an action.
   void PerformAction(Action action);
   // Performs an action after a delay.
   void PerformDelayedAction(Action action, base::TimeDelta delay);
 
-
-
   // Requests a connection to the BattOr.
   void BeginConnect();
 
   // Sends a control message over the connection.
   void SendControlMessage(BattOrControlMessageType type,
                           uint16_t param1,
                           uint16_t param2);
 
+  // Retry the last command.
+  void RetryCommand();
+
   // Completes the command with the specified error.
   void CompleteCommand(BattOrError error);
 
   // Returns a formatted version of samples_ with timestamps and real units.
   std::string SamplesToString();
 
   // The listener that handles the commands' results. It must outlive the agent.
   Listener* listener_;
 
   // The last action executed by the agent. This should only be updated in
@@ skipping 24 matching lines @@
   // The first frame (required for calibration).
   std::vector<RawBattOrSample> calibration_frame_;
 
   // The actual data samples recorded.
   std::vector<RawBattOrSample> samples_;
 
   // The expected sequence number of the next frame. We use this to ensure that
   // we receive frames in order.
   uint32_t next_sequence_number_;
 
-  // The number of times we've attempted to init the BattOr.
-  uint8_t num_init_attempts_;
-
-  // The number of times we've attempted the BattOr StartTracing command.
-  uint8_t num_start_tracing_attempts_;
-
-  // The number of times that we've attempted to read the last message.
-  uint8_t num_read_attempts_;
+  // The number of times we've attempted a command.
+  uint8_t num_command_attempts_;
 
   // The timeout that's run when an action times out.
   base::CancelableClosure timeout_callback_;
 
   // The git hash of the BattOr firmware.
   std::string firmware_git_hash_;
 
   DISALLOW_COPY_AND_ASSIGN(BattOrAgent);
 };
 
 }  // namespace battor
 
 #endif  // TOOLS_BATTOR_AGENT_BATTOR_AGENT_H_