Fix HashTable growth strategy to be 2x instead of 4x

test/mjsunit/ensure-growing-store-learns.js

Index: test/mjsunit/ensure-growing-store-learns.js
diff --git a/test/mjsunit/ensure-growing-store-learns.js b/test/mjsunit/ensure-growing-store-learns.js
index 659ff0d66ec2b395f674177c83f1ee0f54eb8f8f..4ecc9f1cf3ca193b07f554f1f6132ae534d35d41 100644
--- a/test/mjsunit/ensure-growing-store-learns.js
+++ b/test/mjsunit/ensure-growing-store-learns.js
@@ -65,11 +65,11 @@
   assertTrue(%HasFastSmiElements(a));
 
   // Grow a large array into large object space through the keyed store
-  // without deoptimizing. Grow by 10s. If we set elements too sparsely, the
+  // without deoptimizing. Grow by 9s. If we set elements too sparsely, the
   // array will convert to dictionary mode.
   a = new Array(99999);
   assertTrue(%HasFastSmiElements(a));
-  for (var i = 0; i < 263000; i += 10) {
+  for (var i = 0; i < 263000; i += 9) {
     foo2(a, i);
   }