Move all core files in //components/sessions into core/ subdir

components/sessions/session_command.h

-// Copyright 2006 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 COMPONENTS_SESSIONS_SESSION_COMMAND_H_
-#define COMPONENTS_SESSIONS_SESSION_COMMAND_H_
-
-#include <string>
-
-#include "base/basictypes.h"
-#include "components/sessions/sessions_export.h"
-
-namespace base {
-class Pickle;
-}
-
-namespace sessions {
-
-// SessionCommand contains a command id and arbitrary chunk of data. The id
-// and chunk of data are specific to the service creating them.
-//
-// Both TabRestoreService and SessionService use SessionCommands to represent
-// state on disk.
-//
-// There are two ways to create a SessionCommand:
-// . Specifiy the size of the data block to create. This is useful for
-//   commands that have a fixed size.
-// . From a pickle, this is useful for commands whose length varies.
-class SESSIONS_EXPORT SessionCommand {
- public:
-  // These get written to disk, so we define types for them.
-  // Type for the identifier.
-  typedef uint8 id_type;
-
-  // Type for writing the size.
-  typedef uint16 size_type;
-
-  // Creates a session command with the specified id. This allocates a buffer
-  // of size |size| that must be filled via contents().
-  SessionCommand(id_type id, size_type size);
-
-  // Convenience constructor that creates a session command with the specified
-  // id whose contents is populated from the contents of pickle.
-  SessionCommand(id_type id, const base::Pickle& pickle);
-
-  // The contents of the command.
-  char* contents() { return const_cast<char*>(contents_.c_str()); }
-  const char* contents() const { return contents_.c_str(); }
-
-  // Identifier for the command.
-  id_type id() const { return id_; }
-
-  // Size of data.
-  size_type size() const { return static_cast<size_type>(contents_.size()); }
-
-  // Convenience for extracting the data to a target. Returns false if
-  // count is not equal to the size of data this command contains.
-  bool GetPayload(void* dest, size_t count) const;
-
-  // Returns the contents as a pickle. It is up to the caller to delete the
-  // returned Pickle. The returned Pickle references the underlying data of
-  // this SessionCommand. If you need it to outlive the command, copy the
-  // pickle.
-  base::Pickle* PayloadAsPickle() const;
-
- private:
-  const id_type id_;
-  std::string contents_;
-
-  DISALLOW_COPY_AND_ASSIGN(SessionCommand);
-};
-
-}  // namespace sessions
-
-#endif  // COMPONENTS_SESSIONS_SESSION_COMMAND_H_