[test] Fix sanitizer-coverage default options for gyp builds

This was missing in:
TBR=vogelheim@chromium.org

Bug: chromium:710409

TBR=vogelheim@chromium.org
NOTRY=true
Bug: chromium:710409

Change-Id: Ic4b59550e358860cd10adf3d5137342ff7e862a3
Reviewed-on: https://chromium-review.googlesource.com/475831
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44601}

tools/run-tests.py

@@ -419,6 +419,7 @@ def SetupEnvironment(options):
       'coverage=1',
       'coverage_dir=%s' % options.sancov_dir,
       symbolizer,
+      "allow_user_segv_handler=1",
     ])
 
   if options.cfi_vptr: