Don’t install rust-docs, rust-src, or clippy on CI

See https://blog.rust-lang.org/2019/10/15/Rustup-1.20.0.html#profiles

etc/taskcluster/decision_task.py

@@ -190,6 +190,7 @@ def linux_tidy_unit_docs():
             ./etc/ci/lockfile_changed.sh
             ./etc/ci/check_no_panic.sh
 
+            rustup component add rust-docs
             RUSTDOCFLAGS="--disable-minification" ./mach doc
             (
                 cd target/doc
@@ -734,7 +735,6 @@ def windows_task(name):
     )
 
 
-
 def macos_task(name):
     return (
         decisionlib.MacOsGenericWorkerTask(name)

etc/taskcluster/decisionlib.py

@@ -503,7 +503,7 @@ class WindowsGenericWorkerTask(GenericWorkerTask):
         return self \
         .with_path_from_homedir(".cargo\\bin") \
         .with_early_script(
-            "%HOMEDRIVE%%HOMEPATH%\\rustup-init.exe --default-toolchain none -y"
+            "%HOMEDRIVE%%HOMEPATH%\\rustup-init.exe --default-toolchain none --profile=minimal -y"
         ) \
         .with_file_mount("https://win.rustup.rs/x86_64", path="rustup-init.exe")
 
@@ -657,6 +657,8 @@ class MacOsGenericWorkerTask(UnixTaskMixin, GenericWorkerTask):
         return self.with_early_script("""
             export PATH="$HOME/.cargo/bin:$PATH"
             which rustup || curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain none -y
+            rustup self update
+            rustup set profile minimal
         """)
 
 

etc/taskcluster/docker/build.dockerfile

@@ -42,7 +42,7 @@ RUN \
     && \
     #
     #
-    curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain none -y && \
+    curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain none --profile=minimal -y && \
     #
     #
     curl -sSfL \