Auto merge of #18420 - servo:toml, r=nox

Get rustc commit hash from channel manifest

… added in rust-lang/rust#44218, instead of using the GitHub API.

Also upgrade to rustc 1.22.0-nightly (d93036a04 2017-09-07), and app_units 0.5.6 (for servo/app_units#37)

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python/servo/bootstrap_commands.py

@@ -90,12 +90,8 @@ def bootstrap_rustc(self, force=False, target=[], stable=False):
                 base_url = static_s3
             else:
                 import toml
-                import re
                 channel = "%s/%s/channel-rust-nightly.toml" % (static_s3, self.rust_nightly_date())
-                version_string = toml.load(urllib2.urlopen(channel))["pkg"]["rustc"]["version"]
-                short_commit = re.search("\(([0-9a-f]+) ", version_string).group(1)
-                commit_api = "https://api.github.com/repos/rust-lang/rust/commits/" + short_commit
-                nightly_commit_hash = json.load(urllib2.urlopen(commit_api))["sha"]
+                nightly_commit_hash = toml.load(urllib2.urlopen(channel))["pkg"]["rustc"]["git_commit_hash"]
 
                 base_url = "https://s3.amazonaws.com/rust-lang-ci/rustc-builds"
                 if not self.config["build"]["llvm-assertions"]:

rust-toolchain

@@ -1 +1 @@
-nightly-2017-08-31
+nightly-2017-09-08