win: Another attempted fix for toolchain/src skew

TBR=dpranke@chromium.org
R=sebmarchand@chromium.org,davidben@chromium.org

Review URL: https://codereview.chromium.org/1155973003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@295498 0039d316-1c4b-4281-b951-d872f2087c98

win_toolchain/get_toolchain_if_necessary.py

@@ -304,6 +304,8 @@ def main():
       'path': abs_target_dir,
       'version': vs_version,
       'win_sdk': win_sdk,
+      # Added for backwards compatibility with old toolchain packages.
+      'win8sdk': win_sdk,
       'wdk': os.path.join(abs_target_dir, 'wdk'),
       'runtime_dirs': [
         os.path.join(abs_target_dir, 'sys64'),