Synchronization data broken on Vulkan

In the UI (though this issue should not be an UI issue) clicking on a Vulkan subcommands after a `vkCmdWaitEvents` no longer pushes the execution to the `vkSetEvent` where all the pending `VkEvent` as signaled.

Test application: https://github.com/google/vulkan_test_applications/tree/master/application_sandbox/set_event

Clicking on the RenderPass after `vkCmdWaitEvents` no longer shows framebuffer anymore, instead, error: "The framebuffer is not available at this point in the trace" is shown.