Remove bogus flags from call-counts.js test.

The runtime flag in question makes no sense, because the feature cannot
be disabled without keeping the snapshot in sync. We should avoid having
the flag in our "mjsunit" test suite, so that CluserFuzz doesn't pick it
up. The test in question is already skipped, the change will not affect
test results on our waterfall.

R=mvstanton@chromium.org
TEST=mjsunit/call-counts
BUG=v8:4458
LOG=n

Review URL: https://codereview.chromium.org/1409533003

Cr-Commit-Position: refs/heads/master@{#31302}

test/mjsunit/call-counts.js

@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --allow-natives-syntax --noalways-opt --no-vector-stores
+// Flags: --allow-natives-syntax --noalways-opt
 
 // We disable vector store ICs because slot indices change when this option
 // is enabled.

test/mjsunit/mjsunit.status

@@ -252,7 +252,7 @@
   # BUG(v8:3838).
   'regress/regress-3116': [PASS, ['isolates', FLAKY]],
 
-  # BUG(v:4458). TODO(mvstanton): reenable the test once --vector-stores is
+  # BUG(v8:4458). TODO(mvstanton): reenable the test once --vector-stores is
   # prermanently enabled.
   'call-counts': [SKIP],