Remove some unused codes This patch will remove unused functions syncVertexAttributes and hasDirtyOrDynamicAttrib, and private member mAppliedIBChanged. Meanwhile, it changes hasDynamicAttrib to hasActiveDynamicAttrib to avoid unnecessary update in some cases. BUG=angleproject:1155 Change-Id: I29a0aa7fbc13874b7b070cf1ac5ec4134728f519 Reviewed-on: https://chromium-review.googlesource.com/707014 Reviewed-by: Geoff Lang <geofflang@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Geoff Lang <geofflang@chromium.org>