Vulkan: lineloop support for DrawElementsIndirect Add support for lineloops. Includes a compute shader for converting lineloop index buffer with optional restart into linestrip. Test: dEQP.GLES31/functional_draw_indirect_* angle_end2end_tests --gtest_filter=LineLoopIndirectTest.*/* Bug: angleproject:3564 Change-Id: I12d08db1c8d99867f0611e53be50193647695260 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1797106 Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com> Reviewed-by: Tobin Ehlis <tobine@google.com>