Refactoring: de-couple Extensions from "script injection System" [render side] : 1

extensions/common/extension_consumer.h

Index: extensions/common/extension_consumer.h
diff --git a/extensions/common/extension_consumer.h b/extensions/common/extension_consumer.h
new file mode 100644
index 0000000000000000000000000000000000000000..2e06cbb5aadf585d55e024a1b44a839dea70e30e
--- /dev/null
+++ b/extensions/common/extension_consumer.h
@@ -0,0 +1,30 @@
+// 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 EXTENSIONS_COMMON_EXTENSION_CONSUMER_H_
+#define EXTENSIONS_COMMON_EXTENSION_CONSUMER_H_
+
+#include "base/memory/ref_counted.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/host_id.h"
+
+namespace extensions {
+
+// A wrapper class which holds an extension and implements the Host interface.
+class ExtensionConsumer : public Host {

[Devlin, 2015/02/04 17:01:14]

Does this class (and Host itself) have to be in common?  Or can they be in
renderer?

[Xi Han, 2015/02/05 16:06:20]

At least now I think both of them should be in common, since on the browser
side, they also be used by UserScriptLoader etc..

[Devlin, 2015/02/06 00:28:40]

Where are they used by UserScriptLoader, etc?  I only see them used on the
renderer side in this patch.

[Devlin, 2015/02/06 18:48:36]

Didn't get an answer to this one.

[Xi Han, 2015/02/06 19:45:33]

Sorry for missing this comment. Yes, it seems this class in only used the render
side, since we always pass hosd_id along with the ipc from browser to render,
and reconstruct the ExtensionConsumer object in the render. Moved.

+ public:
+  ExtensionConsumer(Extension* extension, const HostID& host_id);

[Devlin, 2015/02/04 17:01:14]

If this is going to store it as a scoped_refptr, it should take in a
scoped_refptr (it's fine to do so by const &).

[Xi Han, 2015/02/05 16:06:20]

Done.

+  ~ExtensionConsumer() override;
+
+  const Extension* extension() const { return extension_.get(); }
+
+ private:
+  scoped_refptr<Extension> extension_;

[Devlin, 2015/02/04 17:01:14]

Extensions should be const.

[Xi Han, 2015/02/05 16:06:20]

Done.

+
+  DISALLOW_COPY_AND_ASSIGN(ExtensionConsumer);
+};
+
+}  // namespace extesions
+
+#endif  // EXTENSIONS_COMMON_EXTENSION_CONSUMER_H_