Add optional creation to ProfileKeyedServiceFactory.

chrome/browser/profiles/profile_keyed_service_factory.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/profiles/profile_keyed_service_factory.h"
 
 #include <vector>
 
 #include "base/memory/singleton.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/profiles/profile_dependency_manager.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
 
 ProfileKeyedServiceFactory::ProfileKeyedServiceFactory(
     ProfileDependencyManager* manager)
     : dependency_manager_(manager), factory_(NULL) {
   dependency_manager_->AddComponent(this);
 }
 
 ProfileKeyedServiceFactory::~ProfileKeyedServiceFactory() {
   dependency_manager_->RemoveComponent(this);
   DCHECK(mapping_.empty());
 }
 
 ProfileKeyedService* ProfileKeyedServiceFactory::GetServiceForProfile(
-    Profile* profile) {
+    Profile* profile,
+    bool create) {
   // Possibly handle Incognito mode.
   if (profile->IsOffTheRecord()) {
     if (ServiceRedirectedInIncognito()) {
       profile = profile->GetOriginalProfile();
     } else if (ServiceHasOwnInstanceInIncognito()) {
       // No-op; the pointers are already set correctly.
     } else {
       return NULL;
     }
   }
 
   ProfileKeyedService* service;
 
   std::map<Profile*, ProfileKeyedService*>::iterator it =
       mapping_.find(profile);
   if (it != mapping_.end()) {
     service = it->second;
-    if (service || !factory_)
+    if (service || !factory_ || !create)
       return service;
 
     // service is NULL but we have a mock factory function
     mapping_.erase(it);
     service = factory_(profile);
+  } else if (create) {
+    // not found but creation allowed
+    service = BuildServiceInstanceFor(profile);
   } else {
-    service = BuildServiceInstanceFor(profile);
+    // not found, creation forbidden
+    return NULL;
   }
 
   Associate(profile, service);
   return service;
 }
 
 void ProfileKeyedServiceFactory::DependsOn(ProfileKeyedServiceFactory* rhs) {
   dependency_manager_->AddEdge(rhs, this);
 }
 
@@ skipping 19 matching lines @@
 }
 
 void ProfileKeyedServiceFactory::ProfileDestroyed(Profile* profile) {
   std::map<Profile*, ProfileKeyedService*>::iterator it =
       mapping_.find(profile);
   if (it != mapping_.end()) {
     delete it->second;
     mapping_.erase(it);
   }
 }