Change to X64 default build in tool scripts in sdk/bin

sdk/bin/pub

 #!/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.
 
 # Run pub.dart on the Dart VM. This script is only used when running pub from
 # within the Dart source repo. The shipped SDK instead uses "pub_sdk", which is
 # renamed to "pub" when the SDK is built.
 
 function follow_links() {
@@ skipping 19 matching lines @@
 declare -a VM_OPTIONS
 
 # Allow extra VM options to be passed in through an environment variable.
 if [[ $DART_VM_OPTIONS ]]; then
   read -a OPTIONS <<< "$DART_VM_OPTIONS"
   VM_OPTIONS+=("${OPTIONS[@]}")
 fi
 
 if [ -z "$DART_CONFIGURATION" ];
 then
-  DART_CONFIGURATION="ReleaseIA32"
+  DART_CONFIGURATION="ReleaseX64"

[Søren Gjesse, 2015/12/17 12:08:34]

ditto.

 fi
 
 if [[ `uname` == 'Darwin' ]];
 then
   BUILD_DIR="$SDK_DIR/../xcodebuild/$DART_CONFIGURATION"
 else
   BUILD_DIR="$SDK_DIR/../out/$DART_CONFIGURATION"
 fi
 
 # Use the Dart binary in the built SDK so pub can find the version file next
 # to it.
 DART="$BUILD_DIR/dart-sdk/bin/dart"
 PACKAGES_DIR="$BUILD_DIR/packages/"
 
 # Run pub.
 PUB="$SDK_DIR/../third_party/pkg/pub/bin/pub.dart"
 exec "$DART" "${VM_OPTIONS[@]}" "--package-root=$PACKAGES_DIR" "$PUB" "$@"