Bug 261259

ImageBufferCreationContext is used in wrong ImageBuffer::create factory function ImageBufferCreationContext is ad hoc amalgamation of all parameters accepted by any ImageBufferBackend, populated for the purpose of constructing a specific backend. ImageBuffer::create<Backend>(..., const ImageBufferCreationContext&) is the concrete function constructing a specific ImageBuffer type with a specific backend. ImageBuffer::create(...) is a polymorphic factory, which invokes the GraphicsClient, a polymorphic interface. It doesn't request a specific backend, rather the polymorphism selects the backend based on policy. This function shouldn't accept ImageBufferCreationContext, there's nothing that can be populated by the caller, except fields incorrectly added to ImageBufferCreationContext.