Refactor renderer-side script injection

extensions/renderer/user_script_injection_list.h

Index: extensions/renderer/user_script_injection_list.h
diff --git a/extensions/renderer/user_script_injection_list.h b/extensions/renderer/user_script_injection_list.h
new file mode 100644
index 0000000000000000000000000000000000000000..bc22bf56e3290e3ffbef550d8a1f30bff85b6dbd
--- /dev/null
+++ b/extensions/renderer/user_script_injection_list.h
@@ -0,0 +1,103 @@
+// 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_INJECTION_LIST_H_
+#define EXTENSIONS_RENDERER_USER_SCRIPT_INJECTION_LIST_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 UserScriptInjectionList is a collection of UserScripts which knows how
+// to update itself from SharedMemory and also knows how to create
+// ScriptInjections for UserScripts to inject on a page.
+class UserScriptInjectionList : public content::RenderProcessObserver {

[not at google - send to devlin, 2014/06/15 23:53:38]

I would say "nit: this class doesn't have List semantics so it should be called
UserScriptSomethingElse" but I've almost gotten used to the code as it is at the
moment, so I'm not sure it's worth the churn to change it. Note that your
comment is "The UserScriptInjectionList is a collection of UserScripts" so why
not UserScriptCollection.

Or "Set"; it's a Set insofar as the order isn't relevant (it may be
deterministic but it's not relevant) and each UserScript is unique, and "set" is
shorter than "collection".

[Devlin, 2014/06/16 18:11:17]

Done.

+ public:
+  class Observer {
+   public:
+    virtual void OnUserScriptsUpdated(
+        const std::set<std::string>& changed_extensions,
+        const std::vector<UserScript*>& scripts) = 0;
+  };
+
+  // Returns the URL to use as the document url when checking permissions for
+  // script injection.
+  static GURL GetDocumentUrlForFrame(blink::WebFrame* frame);

[not at google - send to devlin, 2014/06/15 23:53:38]

this function is only used from script_injection_manager, so it could go an
anonymouse namespace in there.

I swear it was used elsewhere at some point... how odd.

[Devlin, 2014/06/16 18:11:17]

It was in ScriptInjectionManager, but doesn't need to be.  Moved.

+
+  UserScriptInjectionList();
+  virtual ~UserScriptInjectionList();
+
+  // 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,
+                     const GURL& document_url,
+                     const ExtensionSet* extensions);

[not at google - send to devlin, 2014/06/15 23:53:38]

just pass in |extensions| as a constructor/member variable

[Devlin, 2014/06/16 18:11:17]

Done.

+
+ 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 UserScripts this injector manages.
+  ScopedVector<UserScript> scripts_;
+
+  // The associated observers.
+  ObserverList<Observer> observers_;
+
+  DISALLOW_COPY_AND_ASSIGN(UserScriptInjectionList);
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_RENDERER_USER_SCRIPT_INJECTION_LIST_H_