Add infrastructure for skipping tests in GC stress mode.

test/mjsunit/d8-performance-now.js

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 12 matching lines @@
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Flags: --allow-natives-syntax
 
 // Test the performance.now() function of d8.  This test only makes sense with
 // d8.
 
-// Don't run this test in gc stress mode. Time differences may be long
-// due to garbage collections.
-%SetFlags("--gc-interval=-1");
-%SetFlags("--nostress-compaction");
-
 if (this.performance && performance.now) {
   (function run() {
     var start_test = performance.now();
     // Let the retry run for maximum 100ms to reduce flakiness.
     for (var start = performance.now();
         start - start_test < 100;
         start = performance.now()) {
       var end = performance.now();
       assertTrue(start >= start_test);
       assertTrue(end >= start);
       while (end - start == 0) {
         var next = performance.now();
         assertTrue(next >= end);
         end = next;
       }
       if (end - start <= 1) {
         // Found (sub-)millisecond granularity.
         return;
       } else {
         print("Timer difference too big: " + (end - start) + "ms");
       }
     }
     assertTrue(false);
   })()
 }