Vulkan: Don't invalidate XFB buffers on FBO switch. This shouldn't need to change when the FBO changes. Bug: angleproject:4622 Change-Id: I4b06a0f02e8dd16d50aaf5ac5fe4bcb81fc76c8c Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2204597 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Charlie Lao <cclao@google.com> Reviewed-by: Tim Van Patten <timvp@google.com>