Reset limit of map_insert_remove_oom_test and skip on noopt/precompilation.

tests/standalone/map_insert_remove_oom_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
-// VMOptions=--old_gen_heap_size=26
+// VMOptions=--old_gen_heap_size=10
 // Test that compaction does occur on repeated add/remove.
 
 main() {
  var x = {};
- for (int i = 0; i < 10000000; i++) {
+ for (int i = 0; i < 1000000; i++) {
     x[i] = 10;
     x.remove(i);
   }
 }