Add log source to read from one DebugDaemon log

chrome/browser/chromeos/system_logs/single_debug_daemon_log_source.h

+// Copyright 2017 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 CHROME_BROWSER_CHROMEOS_SYSTEM_LOGS_SINGLE_DEBUG_DAEMON_LOG_SOURCE_H_
+#define CHROME_BROWSER_CHROMEOS_SYSTEM_LOGS_SINGLE_DEBUG_DAEMON_LOG_SOURCE_H_
+
+#include <stddef.h>
+
+#include "base/macros.h"
+#include "chrome/browser/feedback/system_logs/system_logs_fetcher.h"
+
+namespace system_logs {
+
+// Gathers log data from a single debugd log source, via DebugDaemonClient.
+class SingleDebugDaemonLogSource : public SystemLogsSource {
+ public:
+  enum class SupportedSource {
+    // For "modetest" command.
+    kModetest,
+
+    // For "lsusb" command.
+    kLsusb,
+  };
+
+  explicit SingleDebugDaemonLogSource(SupportedSource source);
+  ~SingleDebugDaemonLogSource() override;
+
+  // system_logs::SystemLogsSource:
+  void Fetch(const SysLogsSourceCallback& callback) override;
+
+ private:
+  // Callback for handling response from DebugDaemonClient.
+  void OnFetchComplete(const std::string& log_name,
+                       const SysLogsSourceCallback& callback,
+                       bool success,
+                       const std::string& result) const;
+
+  base::WeakPtrFactory<SingleDebugDaemonLogSource> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(SingleDebugDaemonLogSource);
+};
+
+}  // namespace system_logs
+
+#endif  // CHROME_BROWSER_CHROMEOS_SYSTEM_LOGS_SINGLE_DEBUG_DAEMON_LOG_SOURCE_H_