Don't provide system vulkan header paths to Skia.

[chinmaygarde]

Skia privately brings in its own copy. https://skia-review.googlesource.com/c/skia/+/172147

[chinmaygarde]

Not that this PR is to the skia-master branch.

[chinmaygarde]

@liyuqian Are the Cirrus bots wired to take into account the branch from the PR? Or is this still running off of master? I wasn't expecting these jobs to have been triggered.

[liyuqian]

My impression is that Cirrus uses whatever branch your local change is based on. If your local change is based on skia-master, then it uses skia-master. If your local change is based on master, then it uses master. If your local change is based on an old master branch, then it uses that old master branch.

[liyuqian]

BTW, can we also remove flutter/vulkan/skia_vulkan_header.h from our repo since it's no longer used?

[chinmaygarde]

No. We still need that header because the embedder implementation needs the Vulkan headers. We just dont need to forward these over to Skia.