Add OnceCallback support to PostTaskAndReplyWithResult

content/public/browser/browser_thread.h

Index: content/public/browser/browser_thread.h
diff --git a/content/public/browser/browser_thread.h b/content/public/browser/browser_thread.h
index fe82220c1e58fd5c0ed6c5c3f234efe46c276afe..2e36131a90bfe36e29f94ad5376915df4d07d4a9 100644
--- a/content/public/browser/browser_thread.h
+++ b/content/public/browser/browser_thread.h
@@ -142,14 +142,31 @@ class CONTENT_EXPORT BrowserThread {
   static bool PostTaskAndReplyWithResult(
       ID identifier,
       const tracked_objects::Location& from_here,
-      base::Callback<ReturnType()> task,
-      base::Callback<void(ReplyArgType)> reply) {
+      base::OnceCallback<ReturnType()> task,
+      base::OnceCallback<void(ReplyArgType)> reply) {
     scoped_refptr<base::SingleThreadTaskRunner> task_runner =
         GetTaskRunnerForThread(identifier);
     return base::PostTaskAndReplyWithResult(task_runner.get(), from_here,
                                             std::move(task), std::move(reply));
   }
 
+  // Callback version of PostTaskAndReplyWithResult above.
+  // Though RepeatingCallback is convertible to OnceCallback, we need this since
+  // we can not use template deduction and object conversion at once on the
+  // overload resolution.
+  // TODO(tzik): Update all callers of the Callback version to use OnceCallback.

[kinuko, 2017/05/01 04:48:47]

nit: link to the issue?

[tzik, 2017/05/01 05:13:01]

Done.

+  template <typename ReturnType, typename ReplyArgType>
+  static bool PostTaskAndReplyWithResult(
+      ID identifier,
+      const tracked_objects::Location& from_here,
+      base::Callback<ReturnType()> task,
+      base::Callback<void(ReplyArgType)> reply) {
+    return PostTaskAndReplyWithResult(
+        identifier, from_here,
+        static_cast<base::OnceCallback<ReturnType()>>(std::move(task)),
+        static_cast<base::OnceCallback<void(ReplyArgType)>>(std::move(reply)));
+  }
+
   template <class T>
   static bool DeleteSoon(ID identifier,
                          const tracked_objects::Location& from_here,