Do not load extension system in the Profile import process.

chrome/browser/extensions/component_loader.h

Index: chrome/browser/extensions/component_loader.h
diff --git a/chrome/browser/extensions/component_loader.h b/chrome/browser/extensions/component_loader.h
index 02798b31b01616aacd5dc612546214c6831aee61..7e61e0bd652ecb2f4d0a5a349b545ed11b75f934 100644
--- a/chrome/browser/extensions/component_loader.h
+++ b/chrome/browser/extensions/component_loader.h
@@ -32,8 +32,17 @@ class ComponentLoader {
     return component_extensions_.size();
   }
 
-  // Loads any registered component extensions.
-  void LoadAll();
+  // Creates and loads all registered component extensions, including those with
+  // background pages.
+  void BulkLoadAll();
+
+  // Create all registered component extensions, loading those without
+  // background pages and deferring others until a call to BulkLoadDeferred.
+  void BulkLoadDeferBackgroundPages();
+
+  // Load component extensions deferred in the last call to
+  // BulkLoadDeferBackgroundPages.
+  void BulkLoadDeferred();
 
   // Clear the list of all registered extensions and unloads them from the
   // extension service.
@@ -111,7 +120,8 @@ class ComponentLoader {
                   const FilePath& root_directory);
 
   // Loads a registered component extension.
-  const Extension* Load(const ComponentExtensionInfo& info);
+  void Load(const ComponentExtensionInfo& info,
+            bool defer_if_has_background_page);
 
   void AddDefaultComponentExtensionsWithBackgroundPages(
       bool skip_session_components);
@@ -140,6 +150,10 @@ class ComponentLoader {
 
   PrefChangeRegistrar pref_change_registrar_;
 
+  // Extensions with background pages deferred by LoadAll(true).
+  typedef std::vector<scoped_refptr<const Extension> > DeferredAtLoadExtensions;
+  DeferredAtLoadExtensions deferred_at_load_extensions;
+
   DISALLOW_COPY_AND_ASSIGN(ComponentLoader);
 };