Loading Grail's llvm_toolchain with a Chromium sysroot

WORKSPACE

# Change master to the git tag you want.                                                                                                               |
http_archive(                                                                                                                                          |
    name = "com_grail_bazel_toolchain",                                                                                                                |
    strip_prefix = "bazel-toolchain-master",                                                                                                           |
    sha256 = "060d02182794e39033987c4f0b043c653154621ae9d01420aca1a9b63175447a",                                                                       |
    urls = ["https://github.com/grailbio/bazel-toolchain/archive/master.tar.gz"],                                                                      |
)                                                                                                                                                      |
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load("@com_grail_bazel_toolchain//toolchain:deps.bzl", "bazel_toolchain_dependencies")                                                                 |
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bazel_toolchain_dependencies()                                                                                                                         |
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load("@com_grail_bazel_toolchain//toolchain:rules.bzl", "llvm_toolchain")                                                                              |
                                                                                                                                                       |
llvm_toolchain(                                                                                                                                        |
    name = "llvm_toolchain",                                                                                                                           |
    llvm_version = "8.0.0",                                                                                                                            |
    sysroot = {"linux": "@grafica_build//sysroots/debian_sid_amd64-sysroot:sysroot"},                                                                  |
)                                                                                                                                                      |
                                                                                                                                                       |
load("@llvm_toolchain//:toolchains.bzl", "llvm_register_toolchains")                                                                                   |
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llvm_register_toolchains()