Download sysroot from "commondatastorage.googleapis.com"

For some reason our intranet here is blocking googleapis.com.
Actually other tools that are updated via runhooks are using
that alias url already (e.g. clang).

Review URL: https://codereview.chromium.org/1534873002

Cr-Commit-Position: refs/heads/master@{#366481}
diff --git a/build/linux/sysroot_scripts/install-sysroot.py b/build/linux/sysroot_scripts/install-sysroot.py
index b8f34edb..6af6719 100755
--- a/build/linux/sysroot_scripts/install-sysroot.py
+++ b/build/linux/sysroot_scripts/install-sysroot.py
@@ -32,7 +32,7 @@
 import gyp_environment
 
 
-URL_PREFIX = 'http://storage.googleapis.com'
+URL_PREFIX = 'http://commondatastorage.googleapis.com'
 URL_PATH = 'chrome-linux-sysroot/toolchain'
 REVISION_AMD64 = 'bd0a221bc45ed0e70fcce0ce79f6dd86f4dfda07'
 REVISION_ARM = 'bd0a221bc45ed0e70fcce0ce79f6dd86f4dfda07'