This allows extensions like VisualEditor to safely instantiate REST helper objects. It also reduces the number of services that need to be injected into REST handlers from route definitions. Change-Id: I10af85b2da96568cfffd03867d1cb299645fb371
Change-Id: I585f0f23cac5f6dc2a4879f69f7b83828fda3dd3
Bug: T239753 Change-Id: Idf2229255f49514dd8b68bf63573c5b619b4f2f1
Bug: T267981 Change-Id: Ie1a5ee9da5d8231bbf7ea2cbb419ab4bcec33c43