Profiles: Mark the factories as NonThreadSafe and allow services to be deleted on certain threads.

BUG=116892, 116887


Review URL: http://codereview.chromium.org/9617023

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@125282 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 38 insertions, 2 deletions

diff --git a/chrome/browser/profiles/refcounted_profile_keyed_service.h b/chrome/browser/profiles/refcounted_profile_keyed_service.h
index 562e113..c010118 100644
--- a/chrome/browser/profiles/refcounted_profile_keyed_service.h
+++ b/chrome/browser/profiles/refcounted_profile_keyed_service.h
@@ -7,6 +7,17 @@
 
 #include "base/memory/ref_counted.h"
 #include "chrome/browser/profiles/profile_keyed_base.h"
+#include "content/public/browser/browser_thread.h"
+
+class RefcountedProfileKeyedService;
+
+namespace impl {
+
+struct RefcountedProfileKeyedServiceTraits {
+  static void Destruct(const RefcountedProfileKeyedService* obj);
+};
+
+}  // namespace impl
 
 // Base class for refcounted objects that hang off the Profile.
 //
@@ -15,9 +26,16 @@
 // threads. ShutdownOnUIThread() will be called on the UI thread, and then the
 // destructor will run when the last reference is dropped, which may or may not
 // be after the corresponding Profile has been destroyed.
+//
+// Optionally, if you initialize your service with the constructor that takes a
+// thread ID, your service will be deleted on that thread. We can't use
+// content::DeleteOnThread<> directly because RefcountedProfileKeyedService
+// must be one type that RefcountedProfileKeyedServiceFactory can use.
 class RefcountedProfileKeyedService
     : public ProfileKeyedBase,
-      public base::RefCountedThreadSafe<RefcountedProfileKeyedService> {
+      public base::RefCountedThreadSafe<
+          RefcountedProfileKeyedService,
+          impl::RefcountedProfileKeyedServiceTraits> {
  public:
   // Unlike ProfileKeyedService, ShutdownOnUI is not optional. You must do
   // something to drop references during the first pass Shutdown() because this
@@ -26,8 +44,26 @@ class RefcountedProfileKeyedService
   // the UI thread; you do not need to check for that yourself.
   virtual void ShutdownOnUIThread() = 0;
 
-  // This second pass can happen anywhere.
+  // The second pass destruction can happen anywhere unless you specify which
+  // thread this service must be destroyed on by using the second constructor.
   virtual ~RefcountedProfileKeyedService();
+
+ protected:
+  // If you want your service deleted wherever, use the default constructor.
+  RefcountedProfileKeyedService();
+
+  // If you need your service to be deleted on a specific thread (for example,
+  // you're converting a service that used content::DeleteOnThread<IO>), then
+  // use this constructor with the ID of the thread.
+  explicit RefcountedProfileKeyedService(
+      const content::BrowserThread::ID thread_id);
+
+ private:
+  friend struct impl::RefcountedProfileKeyedServiceTraits;
+
+  // Do we have to delete this object on a specific thread?
+  bool requires_destruction_on_thread_;
+  content::BrowserThread::ID thread_id_;
 };
 
 #endif  // CHROME_BROWSER_PROFILES_REFCOUNTED_PROFILE_KEYED_SERVICE_H_