Update SupportsUserData API to accept std::unique_ptr<>.

base/supports_user_data.h

Index: base/supports_user_data.h
diff --git a/base/supports_user_data.h b/base/supports_user_data.h
index a4c7c9fc890bac0692e0d3771a97b9f9c1df401f..21183461d4d420442752d8f23dd7a8139beefe37 100644
--- a/base/supports_user_data.h
+++ b/base/supports_user_data.h
@@ -39,6 +39,7 @@ class BASE_EXPORT SupportsUserData {
   // delete the object if it is changed or the object is destroyed.
   Data* GetUserData(const void* key) const;
   void SetUserData(const void* key, Data* data);

[Nico, 2017/02/10 17:54:25]

add a "// TODO: remove the raw ptr version once everything uses the unique_ptr
version, crbug.com/$your_bug"

+  void SetUserData(const void* key, std::unique_ptr<Data> data);
   void RemoveUserData(const void* key);
 
   // SupportsUserData is not thread-safe, and on debug build will assert it is