Vulkan: Fix Texture attachment state changes. This implements a notification to the Framebuffer that an attachment had a state change that might require recreating the VkFramebuffer. This implementation is much simpler than the prior method with signal notifications. Only currently implemented for TextureVk but will also be implemented for RenderbufferVk. Bug: angleproject:2347 Change-Id: I05f7da4132f6ed2bda02671e8ba5ee9805252928 Reviewed-on: https://chromium-review.googlesource.com/930024 Reviewed-by: Luc Ferron <lucferron@google.com> Reviewed-by: Yuly Novikov <ynovikov@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>