Move channel-related (Chrome-specific) global state out of Feature.

chrome/common/extensions/features/feature_channel.h

+// Copyright 2013 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_COMMON_EXTENSIONS_FEATURES_FEATURE_CHANNEL_H_
+#define CHROME_COMMON_EXTENSIONS_FEATURES_FEATURE_CHANNEL_H_
+
+#include "chrome/common/chrome_version_info.h"
+
+namespace extensions {
+
+// Gets the current channel as seen by the Feature system.
+chrome::VersionInfo::Channel GetCurrentChannel();
+
+// Sets the current channel as seen by the Feature system. In the browser
+// process this should be chrome::VersionInfo::GetChannel(), and in the
+// renderer this will need to come from an IPC.
+void SetCurrentChannel(chrome::VersionInfo::Channel channel);
+
+// Gets the default channel as seen by the Feature system.
+chrome::VersionInfo::Channel GetDefaultChannel();
+
+// Scoped channel setter. Use for tests.
+class ScopedCurrentChannel {
+ public:
+  explicit ScopedCurrentChannel(chrome::VersionInfo::Channel channel)
+      : original_channel_(chrome::VersionInfo::CHANNEL_UNKNOWN) {
+    original_channel_ = GetCurrentChannel();
+    SetCurrentChannel(channel);
+  }
+
+  ~ScopedCurrentChannel() {
+    SetCurrentChannel(original_channel_);
+  }
+
+ private:
+  chrome::VersionInfo::Channel original_channel_;
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_COMMON_EXTENSIONS_FEATURES_FEATURE_CHANNEL_H_