Revert "Move dart2js from sdk/lib/_internal/compiler to pkg/compiler"

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")"
-  done
-  echo "$file"
-}
-
-# Unlike $0, $BASH_SOURCE points to the absolute path of this file.
-PROG_NAME="$(follow_links "$BASH_SOURCE")"
-
-# Handle the case where dart-sdk/bin has been symlinked to.
-BIN_DIR="$(cd "${PROG_NAME%/*}" ; pwd -P)"
-
-SDK_DIR="$(cd "${BIN_DIR}/.." ; pwd -P)"
-
-DART="$BIN_DIR/dart"
-
-SNAPSHOT_DIR="$BIN_DIR/snapshots"
-SNAPSHOT="$SNAPSHOT_DIR/dart2js.dart.snapshot"
-
-unset EXTRA_OPTIONS
-declare -a EXTRA_OPTIONS
-
-if test -t 1; then
-  # Stdout is a terminal.
-  if test 8 -le `tput colors`; then
-    # Stdout has at least 8 colors, so enable colors.
-    EXTRA_OPTIONS+=('--enable-diagnostic-colors')
-  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" "${EXTRA_OPTIONS[@]}" "$@"