Declarative content scripts: Browser-side: per-extension shared memory regions (lazily loaded)

chrome/browser/extensions/declarative_user_script_master.h

Index: chrome/browser/extensions/declarative_user_script_master.h
diff --git a/chrome/browser/extensions/declarative_user_script_master.h b/chrome/browser/extensions/declarative_user_script_master.h
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+++ b/chrome/browser/extensions/declarative_user_script_master.h
@@ -0,0 +1,78 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.

[Devlin, 2014/07/30 21:20:38]

nit: we don't use (c) anymore (I don't know why, but there's some complicated
legal reason ;))

[Mark Dittmer, 2014/07/31 18:37:33]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_DECLARATIVE_USER_SCRIPT_MASTER_H_
+#define CHROME_BROWSER_EXTENSIONS_DECLARATIVE_USER_SCRIPT_MASTER_H_
+
+#include <set>
+
+#include "base/scoped_observer.h"

[Devlin, 2014/07/30 21:20:38]

unused?

[Mark Dittmer, 2014/07/31 18:37:33]

Done.

+#include "chrome/browser/extensions/user_script_master.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+#include "extensions/common/extension.h"
+
+class Profile;
+
+namespace extensions {
+
+class DeclarativeUserScriptMaster : public UserScriptMaster,
+                                    public content::NotificationObserver {
+ public:
+  DeclarativeUserScriptMaster(Profile* profile,
+                              const ExtensionId& extension_id);
+  virtual ~DeclarativeUserScriptMaster();
+
+  // content::NotificationObserver implementation.
+  virtual void Observe(int type,

[Devlin, 2014/07/30 21:20:38]

Let's make this private.

[Mark Dittmer, 2014/07/31 18:37:33]

Done.

+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  // Add script to shared memory region. This may not happen right away if a
+  // script load is in progress.
+  void AddScript(const UserScript& script);
+
+  // Remove script from shared memory region. This may not happen right away if
+  // a script load is in progress.
+  void RemoveScript(const UserScript& script);
+
+  // Remove all scripts from shared memory region. This may not happen right
+  // away if a script load is in progress.
+  void ClearScripts();
+
+  // Start loading scripts into shared memory region.

[Devlin, 2014/07/30 21:20:38]

Replace this comment with just UserScriptMaster implementation.  We try to only
document these in one place so that if they ever change, we only have to update
one comment.

[Mark Dittmer, 2014/07/31 18:37:33]

Done.

+  virtual void StartLoad() OVERRIDE;
+
+ private:
+  // Reset UserScriptMaster::pending_load_ based on our data.
+  void ResetPendingLoad() {

[Devlin, 2014/07/30 21:20:38]

This and ResetPendingLoadData should probably both be in the .cc (more style
than anything else, since they are both very simple).

[Mark Dittmer, 2014/07/31 18:37:33]

Done.

+    pending_load_ = (clear_scripts_ || scripts_to_add_.size() > 0 ||
+                     scripts_to_remove_.size() > 0);
+  }
+
+  // Reset data upon which UserScriptMaster::pending_load_ depends.
+  void ResetPendingLoadData() {
+    scripts_to_add_.clear();
+    scripts_to_remove_.clear();
+    clear_scripts_ = false;
+  }
+
+  // Scripts to be added next time the memory region reloads.
+  std::set<UserScript> scripts_to_add_;
+
+  // Scripts to be removed next time the memory region reloads.
+  std::set<UserScript> scripts_to_remove_;
+
+  // Indicator variable: clear list of scripts on next reload.
+  bool clear_scripts_;
+
+  // Manages our notification registrations.
+  content::NotificationRegistrar registrar_;
+
+  DISALLOW_COPY_AND_ASSIGN(DeclarativeUserScriptMaster);
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_DECLARATIVE_USER_SCRIPT_MASTER_H_