[test] Speed up some slow tests.

test/mjsunit/math-floor-part4.js

Index: test/mjsunit/math-floor-part4.js
diff --git a/test/mjsunit/math-floor-part4.js b/test/mjsunit/math-floor-part4.js
index 9ae83d87c6259c090c9cd1a44504ed005a830aea..499200288e3e4943c54bc6ca284060814b0b5323 100644
--- a/test/mjsunit/math-floor-part4.js
+++ b/test/mjsunit/math-floor-part4.js
@@ -93,11 +93,11 @@ function test() {
 
 
 // Test in a loop to cover the custom IC and GC-related issues.
-for (var i = 0; i < 100; i++) {
+for (var i = 0; i < 10; i++) {
   test();
+  new Array(i * 10000);
 }
 
-
 // Regression test for a bug where a negative zero coming from Math.floor
 // was not properly handled by other operations.
 function floorsum(i, n) {