Append function name/offset to kernel warning signature.

The current crash reporter signature for a kernel warning
is the 8-digit hex hash for the warning.  For convenience,
add the function name + offset to the hash, when it is
available.

BUG=chromium:328948
TEST=ran unit test

Change-Id: I8f047497c0556227a1dbdf650dabcd4c51aa8340
Reviewed-on: https://chromium-review.googlesource.com/180320
Tested-by: Luigi Semenzato <semenzato@chromium.org>
Reviewed-by: Sameer Nanda <snanda@chromium.org>
Commit-Queue: Luigi Semenzato <semenzato@chromium.org>
diff --git a/crash_reporter/warn_collector_test.sh b/crash_reporter/warn_collector_test.sh
index 0790181..d9bb6f9 100755
--- a/crash_reporter/warn_collector_test.sh
+++ b/crash_reporter/warn_collector_test.sh
@@ -38,7 +38,7 @@
     fail "expected ${n_expected} lines in ${TESTLOG}, found this instead:
 $(<"${TESTLOG}")"
   fi
-  if egrep -qv '^[0-9a-f]{8}$' "${TESTLOG}"; then
+  if egrep -qv '^[0-9a-f]{8}' "${TESTLOG}"; then
     fail "found bad lines in ${TESTLOG}:
 $(<"${TESTLOG}")"
   fi