Add asm.js to build_config.h.

Bug: 804907
Change-Id: I194c59129cad52b0775181d8582c9529590af74f
Reviewed-on: https://chromium-review.googlesource.com/870813
Commit-Queue: Henrique Nakashima <[email protected]>
Reviewed-by: Jochen Eisinger <[email protected]>
Cr-Commit-Position: refs/heads/master@{#531574}
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index d5f392a..31f71c6 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -491,6 +491,7 @@
     # Please keep sorted.
     'OS_AIX',
     'OS_ANDROID',
+    'OS_ASMJS',
     'OS_BSD',
     'OS_CAT',       # For testing.
     'OS_CHROMEOS',