Unrolled build for #153476

Rollup merge of #153476 - DanielEScherzer:patch-2, r=bjorn3

bootstrap.py: fix typo "parallle"

Author: rust-timer

src/bootstrap/bootstrap.py

@@ -696,7 +696,7 @@ def download_toolchain(self):
             for download_info in tarballs_download_info:
                 download_component(download_info)
 
-            # Unpack the tarballs in parallle.
+            # Unpack the tarballs in parallel.
             # In Python 2.7, Pool cannot be used as a context manager.
             pool_size = min(len(tarballs_download_info), get_cpus())
             if self.verbose: