dart2js: Remove heap-growth-flag that was passed to the VM.

sdk/bin/dart2js_sdk

 #!/bin/bash
 # Copyright (c) 2012, 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.
 
 function follow_links() {
   file="$1"
   while [ -h "$file" ]; do
     # On Mac OS, readlink -f doesn't work.
     file="$(readlink "$file")"
@@ skipping 25 matching lines @@
   fi
 fi
 
 unset EXTRA_VM_OPTIONS
 declare -a EXTRA_VM_OPTIONS
 
 if test -f "$SNAPSHOT"; then
   EXTRA_OPTIONS+=("--library-root=$SDK_DIR")
 fi
 
-# Tell the VM to grow the heap more aggressively. This should only
-# be necessary temporarily until the VM is better at detecting how
-# applications use memory.
-# TODO(ahe): Remove this option (http://dartbug.com/6495).
-EXTRA_VM_OPTIONS[${#EXTRA_VM_OPTIONS[@]}]='--heap_growth_rate=512'
-
 case $0 in
   *_developer)
     EXTRA_VM_OPTIONS+=('--checked')
     ;;
 esac
 
 # We allow extra vm options to be passed in through an environment variable.
 if [[ $DART_VM_OPTIONS ]]; then
   read -a OPTIONS <<< "$DART_VM_OPTIONS"
   EXTRA_VM_OPTIONS+=("${OPTIONS[@]}")
 fi
 
 exec "$DART" "${EXTRA_VM_OPTIONS[@]}" "$SNAPSHOT" "${EXTRA_OPTIONS[@]}" "$@"