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

chrome/browser/extensions/user_script_master.h

Index: chrome/browser/extensions/user_script_master.h
diff --git a/chrome/browser/extensions/user_script_master.h b/chrome/browser/extensions/user_script_master.h
index 3252a8417fc1a998064890b729fedc9db2b538b2..a41562a08b6e9b91ab2821202c83f27ba22c7acc 100644
--- a/chrome/browser/extensions/user_script_master.h
+++ b/chrome/browser/extensions/user_script_master.h
@@ -11,11 +11,7 @@
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
-#include "base/scoped_observer.h"
 #include "content/public/browser/browser_thread.h"
-#include "content/public/browser/notification_observer.h"
-#include "content/public/browser/notification_registrar.h"
-#include "extensions/browser/extension_registry_observer.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/common/extension_set.h"
 #include "extensions/common/user_script.h"
@@ -40,8 +36,7 @@ typedef std::map<std::string, ExtensionSet::ExtensionPathAndDefaultLocale>
 
 // Manages a segment of shared memory that contains the user scripts the user
 // has installed.  Lives on the UI thread.
-class UserScriptMaster : public content::NotificationObserver,
-                         public ExtensionRegistryObserver {
+class UserScriptMaster {
  public:
   // Parses the includes out of |script| and returns them in |includes|.
   static bool ParseMetadataHeader(const base::StringPiece& script_text,
@@ -56,7 +51,7 @@ class UserScriptMaster : public content::NotificationObserver,
 
   // Kicks off a process on the file thread to reload scripts from disk
   // into a new chunk of shared memory and notify renderers.
-  virtual void StartLoad();
+  virtual void StartLoad() = 0;
 
   // Gets the segment of shared memory for the scripts.
   base::SharedMemory* GetSharedMemory() const {
@@ -66,24 +61,27 @@ class UserScriptMaster : public content::NotificationObserver,
   // Return true if we have any scripts ready.
   bool ScriptsReady() const { return shared_memory_.get() != NULL; }
 
- private:
-  // content::NotificationObserver implementation.
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) OVERRIDE;
-
-  // ExtensionRegistryObserver implementation.
-  virtual void OnExtensionLoaded(content::BrowserContext* browser_context,
-                                 const Extension* extension) OVERRIDE;
-  virtual void OnExtensionUnloaded(
-      content::BrowserContext* browser_context,
-      const Extension* extension,
-      UnloadedExtensionInfo::Reason reason) OVERRIDE;
-
   // Called once we have finished loading the scripts on the file thread.
   void OnScriptsLoaded(scoped_ptr<UserScriptList> user_scripts,
                        scoped_ptr<base::SharedMemory> shared_memory);
 
+ protected:
+  typedef base::Callback<
+      void(scoped_ptr<UserScriptList>, scoped_ptr<base::SharedMemory>)>
+      LoadScriptsCallback;
+
+  static void LoadScriptsOnFileThread(
+      scoped_ptr<UserScriptList> user_scripts,
+      const ExtensionsInfo& extensions_info,
+      const std::set<std::string>& new_extensions,
+      scoped_refptr<ContentVerifier> verifier,
+      LoadScriptsCallback callback);
+
+  bool is_loading() const {
+    // Ownership of |user_scripts_| is passed to the file thread when loading.
+    return user_scripts_.get() == NULL;
+  }
+
   // Sends the renderer process a new set of user scripts. If
   // |changed_extensions| is not empty, this signals that only the scripts from
   // those extensions should be updated. Otherwise, all extensions will be
@@ -92,17 +90,6 @@ class UserScriptMaster : public content::NotificationObserver,
                   base::SharedMemory* shared_memory,
                   const std::set<std::string>& changed_extensions);
 
-  bool is_loading() const {
-    // Ownership of |user_scripts_| is passed to the file thread when loading.
-    return user_scripts_.get() == NULL;
-  }
-
-  // Manages our notification registrations.
-  content::NotificationRegistrar registrar_;
-
-  // Contains the scripts that were found the last time scripts were updated.
-  scoped_ptr<base::SharedMemory> shared_memory_;
-
   // List of scripts from currently-installed extensions we should load.
   scoped_ptr<UserScriptList> user_scripts_;
 
@@ -127,18 +114,23 @@ class UserScriptMaster : public content::NotificationObserver,
   // finishes.  This boolean tracks whether another load is pending.
   bool pending_load_;
 
-  // Whether or not we are currently loading.
-  bool is_loading_;
-
   // The profile for which the scripts managed here are installed.
   Profile* profile_;
 
-  // Listen to extension load, unloaded notifications.
-  ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
-      extension_registry_observer_;
-
   base::WeakPtrFactory<UserScriptMaster> weak_factory_;
 
+  // ID of extension that owns this region, if any. This is the empty string in
+  // the case of the memory region for statically declared content scripts,
+  // which is shared between extensions.
+  ExtensionId owner_extension_id_;
+
+ private:
+  // Contains the scripts that were found the last time scripts were updated.
+  scoped_ptr<base::SharedMemory> shared_memory_;
+
+  // Whether or not we are currently loading.
+  bool is_loading_;
+
   DISALLOW_COPY_AND_ASSIGN(UserScriptMaster);
 };