Add and use a clang_linux asset.

infra/bots/recipes/swarm_trigger.py

Index: infra/bots/recipes/swarm_trigger.py
diff --git a/infra/bots/recipes/swarm_trigger.py b/infra/bots/recipes/swarm_trigger.py
index f512f770d6ec6ca5a6de3e1af5d78a9f87042df9..7b3bf9eb47bea3896b2eed29db94c75fce055fa5 100644
--- a/infra/bots/recipes/swarm_trigger.py
+++ b/infra/bots/recipes/swarm_trigger.py
@@ -354,13 +354,17 @@ def compile_steps_swarm(api, builder_cfg, got_revision, infrabots_dir):
   cipd_packages = []
 
   # Android bots require a toolchain.
-  if 'Android' in api.properties['buildername']:
+  if 'Android' in builder_name:
     cipd_packages.append(cipd_pkg(api, infrabots_dir, 'android_sdk'))
-    if 'Mac' in api.properties['buildername']:
+    if 'Mac' in builder_name:
       cipd_packages.append(cipd_pkg(api, infrabots_dir, 'android_ndk_darwin'))
     else:
       cipd_packages.append(cipd_pkg(api, infrabots_dir, 'android_ndk_linux'))
 
+  if 'Ubuntu' in builder_name and (
+      'SAN' in builder_name or 'Clang' in builder_name):
+    cipd_packages.append(cipd_pkg(api, infrabots_dir, 'clang_linux'))
+
   # Windows bots require a toolchain.
   if 'Win' in builder_name:
     version_file = infrabots_dir.join('assets', 'win_toolchain', 'VERSION')