[battor_agent] Clear pending read buffer if it contains an irrevocable error.

tools/battor_agent/battor_connection_impl.cc

 // 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.
 
 #include "tools/battor_agent/battor_connection_impl.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/memory/ptr_util.h"
@@ skipping 240 matching lines @@
       return;
     }
 
     LogSerial("(Message still incomplete: reading more bytes.)");
     BeginReadBytes(message_max_bytes - already_read_buffer_.size());
     return;
   }
 
   if (parse_message_error != ParseMessageError::NONE) {
     LogSerial(StringPrintf(
-        "Read failed due to the message containing an irrecoverable error: %d.",
+        "Read failed due to the message containing an irrecoverable error: %d, "
+        "clearing the pending read buffer.",
         parse_message_error));
+    already_read_buffer_.clear();
     EndReadBytes(false, BATTOR_MESSAGE_TYPE_CONTROL, nullptr);
     return;
   }
 
   if (type != pending_read_message_type_) {
     LogSerial("Read failed due to receiving a message of the wrong type.");
     EndReadBytes(false, BATTOR_MESSAGE_TYPE_CONTROL, nullptr);
     return;
   }
 
@@ skipping 71 matching lines @@
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE,
       base::Bind(&Listener::OnBytesSent, base::Unretained(listener_), success));
 }
 
 void BattOrConnectionImpl::LogSerial(const std::string& str) {
   serial_log_ << str << std::endl << std::endl;
 }
 
 }  // namespace battor