Count number of origins with data affected by clearing "cookies and site data".

content/browser/dom_storage/dom_storage_context_impl.cc

Index: content/browser/dom_storage/dom_storage_context_impl.cc
diff --git a/content/browser/dom_storage/dom_storage_context_impl.cc b/content/browser/dom_storage/dom_storage_context_impl.cc
index 2b945dea40fc23536b5d7a92c92dc133fcad4fa0..9daad33aa26e9c1b367ca588fd2faad7ba62552e 100644
--- a/content/browser/dom_storage/dom_storage_context_impl.cc
+++ b/content/browser/dom_storage/dom_storage_context_impl.cc
@@ -256,6 +256,15 @@ void DOMStorageContextImpl::DeleteSessionStorage(
     dom_storage_namespace = GetStorageNamespace(namespace_id);
   }
   dom_storage_namespace->DeleteSessionStorageOrigin(usage_info.origin);
+  // TODO? This removes remaining traces of deleted sessions but I don't know if
+  // it could interfere with whatever happens with this clear event below?
+  /*if (session_storage_database_.get()) {

[msramek, 2017/01/09 12:54:44]

Since you already know how to solve it, just need a confirmation from the code
owners that it's the right thing, I'd suggest extracting this to a separate CL.

[dullweber, 2017/01/09 16:05:46]

I created https://codereview.chromium.org/2622603002

+    task_runner_->PostShutdownBlockingTask(
+        FROM_HERE, DOMStorageTaskRunner::COMMIT_SEQUENCE,
+        base::Bind(base::IgnoreResult(&SessionStorageDatabase::DeleteArea),
+                   session_storage_database_,
+                   usage_info.persistent_namespace_id, usage_info.origin));
+  }*/
   // Synthesize a 'cleared' event if the area is open so CachedAreas in
   // renderers get emptied out too.
   DOMStorageArea* area =