Properly propagate the current Chrome channel into the Feature system on the

chrome/common/extensions/features/feature.h

Index: chrome/common/extensions/features/feature.h
diff --git a/chrome/common/extensions/features/feature.h b/chrome/common/extensions/features/feature.h
index 2683d5b8f999dcb592f80f5606ff7495f27af845..bf315acac6ef6f1e793f39224dbfd530a84dd96c 100644
--- a/chrome/common/extensions/features/feature.h
+++ b/chrome/common/extensions/features/feature.h
@@ -68,23 +68,44 @@ class Feature {
   Feature(const Feature& other);
   virtual ~Feature();
 
-  // (Re)Sets whether checking against "channel" should be done. This must only
-  // be called on the browser process, since the check involves accessing the
-  // filesystem.
-  // See http://crbug.com/126535.
-  static void SetChannelCheckingEnabled(bool enabled);
-  static void ResetChannelCheckingEnabled();
-
-  // (Re)Sets the Channel to for all Features to compare against. This is
-  // usually chrome::VersionInfo::GetChannel(), but for tests allow this to be
-  // overridden.
-  static void SetChannelForTesting(chrome::VersionInfo::Channel channel);
-  static void ResetChannelForTesting();
-
-  // Returns the current channel as seen by the Feature system (i.e. the
-  // ChannelForTesting if one is set, otherwise the actual channel).
+  // Returns true if a channel has been set.
+  static bool HasCurrentChannel();
+
+  // Gets the current channel as seen by the Feature system.
+  // SetCurrentChannel() must have already been called.
   static 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.
+  static void SetCurrentChannel(chrome::VersionInfo::Channel channel);
+
+  // Clears the current channel as seen by the Feature system.
+  static void ClearCurrentChannel();
+
+  // Scoped channel setter. Use for tests.
+  class ScopedCurrentChannel {
+   public:
+    explicit ScopedCurrentChannel(chrome::VersionInfo::Channel channel)
+        : has_original_channel_(false),
+          original_channel_(chrome::VersionInfo::CHANNEL_UNKNOWN) {
+      if (HasCurrentChannel()) {
+        has_original_channel_ = true;
+        original_channel_ = GetCurrentChannel();
+      }
+      SetCurrentChannel(channel);
+    }
+
+    ~ScopedCurrentChannel() {
+      if (has_original_channel_)
+        SetCurrentChannel(original_channel_);

[Matt Perry, 2012/08/08 19:17:26]

else: ClearCurrentChannel?

[not at google - send to devlin, 2012/08/09 00:14:37]

Oops. Thanks.

+    }
+
+   private:
+    bool has_original_channel_;
+    chrome::VersionInfo::Channel original_channel_;
+  };
+
   const std::string& name() const { return name_; }
   void set_name(const std::string& name) { name_ = name; }