[test] Run the future variant on a subset of bots.

TBR=sergiyb@chromium.org

Bug: chromium:786938,v8:7106
Change-Id: Id60354be899187e4c09d53434ad70019c857f9e9
Reviewed-on: https://chromium-review.googlesource.com/779725
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49511}

test/mjsunit/mjsunit.status

@@ -651,6 +651,7 @@
 ['variant == future', {
   # BUG(v8:7106).
   'regress/typed-array-lifetime': [SKIP],
+  'regress/regress-2249': [SKIP],
 }],  # variant == future
 
 ##############################################################################

tools/testrunner/standard_runner.py

@@ -48,7 +48,7 @@ VARIANT_ALIASES = {
   # Additional variants, run on all bots.
   "more": MORE_VARIANTS,
   # Additional variants, run on a subset of bots.
-  "extra": [],
+  "extra": ["future"],
 }
 
 GC_STRESS_FLAGS = ["--gc-interval=500", "--stress-compaction",