Refactor renderer-side script injection

extensions/renderer/user_script_set.h

Index: extensions/renderer/user_script_set.h
diff --git a/extensions/renderer/user_script_set.h b/extensions/renderer/user_script_set.h
new file mode 100644
index 0000000000000000000000000000000000000000..48fc641298eb4ca99cfc4d4af6269e0d6661c72f
--- /dev/null
+++ b/extensions/renderer/user_script_set.h
@@ -0,0 +1,100 @@
+// Copyright 2014 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_RENDERER_USER_SCRIPT_SET_H_
+#define EXTENSIONS_RENDERER_USER_SCRIPT_SET_H_
+
+#include <set>
+#include <string>
+
+#include "base/basictypes.h"
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/scoped_vector.h"
+#include "base/memory/shared_memory.h"
+#include "base/observer_list.h"
+#include "content/public/renderer/render_process_observer.h"
+#include "extensions/common/user_script.h"
+
+class GURL;
+
+namespace blink {
+class WebFrame;
+}
+
+namespace extensions {
+class Extension;
+class ExtensionSet;
+class ScriptInjection;
+
+// The UserScriptSet is a collection of UserScripts which knows how to update
+// itself from SharedMemory and create ScriptInjections for UserScripts to
+// inject on a page.
+class UserScriptSet : public content::RenderProcessObserver {
+ public:
+  class Observer {
+   public:
+    virtual void OnUserScriptsUpdated(
+        const std::set<std::string>& changed_extensions,
+        const std::vector<UserScript*>& scripts) = 0;
+  };
+
+  UserScriptSet(const ExtensionSet* extensions);
+  virtual ~UserScriptSet();
+
+  // Adds or removes observers.
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  // Appends the ids of the extensions that have user scripts to |ids|.
+  void GetActiveExtensionIds(std::set<std::string>* ids) const;
+
+  // Populate |injections| with any ScriptInjections that should run on the
+  // given |web_frame| and |tab_id|, at the given |run_location|.
+  // |extensions| is passed in to verify the corresponding extension is still
+  // valid.
+  void GetInjections(ScopedVector<ScriptInjection>* injections,
+                     blink::WebFrame* web_frame,
+                     int tab_id,
+                     UserScript::RunLocation run_location);
+
+ private:
+  // content::RenderProcessObserver implementation.
+  virtual bool OnControlMessageReceived(const IPC::Message& message) OVERRIDE;
+
+  // Handle the UpdateUserScripts extension message.
+  void OnUpdateUserScripts(base::SharedMemoryHandle shared_memory,
+                           const std::set<std::string>& changed_extensions);
+
+  // Update the parsed scripts from |shared memory|.
+  bool UpdateScripts(base::SharedMemoryHandle shared_memory);
+
+  // Returns a new ScriptInjection for the given |script| to execute in the
+  // |web_frame|, or NULL if the script should not execute.
+  scoped_ptr<ScriptInjection> GetInjectionForScript(
+      UserScript* script,
+      blink::WebFrame* web_frame,
+      int tab_id,
+      UserScript::RunLocation run_location,
+      const GURL& document_url,
+      const Extension* extension);
+
+  // Shared memory containing raw script data.
+  scoped_ptr<base::SharedMemory> shared_memory_;
+
+  // The set of all known extensions. Owned by the Dispatcher.
+  const ExtensionSet* extensions_;
+
+  // The UserScripts this injector manages.
+  ScopedVector<UserScript> scripts_;
+
+  // The associated observers.
+  ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserScriptSet);
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_RENDERER_USER_SCRIPT_SET_H_