Refactor all the Bind* GLES 2.0 entry points. This requires storing a reference the the Context's Framebuffer map in the ValidationContext. Likely we'll need to do this as well for the other non-shared object types. BUG=angleproject:747 Change-Id: I73ee8b0be3c3b9e54b7e48e49d6f738cf1d926dd Reviewed-on: https://chromium-review.googlesource.com/407843 Commit-Queue: Jamie Madill <jmadill@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>