Componentize VersionInfo.

components/version_info/version_info.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 COMPONENTS_VERSION_INFO_VERSION_INFO_H_
+#define COMPONENTS_VERSION_INFO_VERSION_INFO_H_
+
+#include <string>
+
+#include "base/macros.h"
+
+namespace version_info {
+
+// The possible channels for an installation, from most fun to most stable.
+enum Channel {

[dzhioev (left Google), 2015/07/28 18:33:49]

I suggest to replace this enum with a strongly typed enum (enum class), as long
as we are changing Channel usage everywhere anyway. "CHANNEL_" prefix can be
dropped, so the items will be referenced as follows
"version_info::Channel::STABLE".

+  CHANNEL_UNKNOWN = 0,
+  CHANNEL_CANARY,
+  CHANNEL_DEV,
+  CHANNEL_BETA,
+  CHANNEL_STABLE,
+};
+
+// Returns the product name and version information for UserAgent header,
+// e.g. "Chrome/a.b.c.d".
+std::string GetProductNameAndVersionForUserAgent();
+
+// Returns the product name, e.g. "Chromium" or "Google Chrome".
+std::string GetProductName();
+
+// Returns the version number, e.g. "6.0.490.1".
+std::string GetVersionNumber();
+
+// Returns a version control specific identifier of this release.
+std::string GetLastChange();
+
+// Returns whether this is an "official" release of the current version, i.e.
+// whether kwnowing GetVersionNumber() is enough to completely determine what
+// GetLastChange() is.
+bool IsOfficialBuild();
+
+// Returns the OS type, e.g. "Windows", "Linux", "FreeBDS", ...
+std::string GetOSType();
+
+// Returns a string equivalent of |channel|, indenpendent of whether the build
+// is branded or not and without any additional modifiers.
+std::string GetChannelString(Channel channel);
+
+// Returns a version string to be displayed in "About Chromium" dialog.
+// |modifier| is a string representation of the channel with system specific
+// information, e.g. "dev SyzyASan". It is appended to the returned version
+// information if non-empty.
+std::string GetVersionStringWithModifier(const std::string& modifier);
+
+}  // namespace version_info
+
+#endif  // COMPONENTS_VERSION_INFO_VERSION_INFO_H_