Vulkan: Fix dirty element array buffer updates. The issue occurs that binds the same buffer and calls glDrawElements with the same indices. The offset has been reset in the VertexArrayVk::syncState(), but it doesn't check the actual value in the ContextVk::setupIndexedDraw(). Also corrected case where update via BufferSubData wasn't being sent to the HW. Bug: angleproject:3362 Change-Id: I0f7d2fc162bc8f1c36cb09ba689fd27b482b9035 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1666345 Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>