Remove download_dart_sdk.py

This script is not used anymore.

infra/.gitignore

diff --git a/infra/.gitignore b/infra/.gitignore
index bc2309e..42c973a 100644
--- a/infra/.gitignore
+++ b/infra/.gitignore
@@ -1,4 +1,3 @@
 .recipe_deps
-dart-sdk
 android_tools
 *.pyc

infra/download_dart_sdk.py

diff --git a/infra/download_dart_sdk.py b/infra/download_dart_sdk.py
deleted file mode 100755
index 63a1d8d..0000000
--- a/infra/download_dart_sdk.py
+++ /dev/null
@@ -1,99 +0,0 @@
-#!/usr/bin/python
-# Copyright 2015 The Chromium Authors. All rights reserved.
-# Use of this source code is governed by a BSD-style license that can be
-# found in the LICENSE file.
-
-"""Pulls down the current dart sdk to third_party/dart-sdk/.
-
-You can manually force this to run again by removing
-third_party/dart-sdk/STAMP_FILE, which contains the URL of the SDK that
-was downloaded. Rolling works by updating LINUX_64_SDK to a new URL.
-"""
-
-import os
-import shutil
-import subprocess
-import sys
-
-# How to roll the dart sdk: Just change this url! We write this to the stamp
-# file after we download, and then check the stamp file for differences.
-SDK_URL_BASE = ('http://gsdview.appspot.com/dart-archive/channels/stable/raw/'
-                '1.14.1/sdk/')
-
-LINUX_64_SDK = 'dartsdk-linux-x64-release.zip'
-MACOS_64_SDK = 'dartsdk-macos-x64-release.zip'
-
-# Path constants. (All of these should be absolute paths.)
-THIS_DIR = os.path.abspath(os.path.dirname(__file__))
-DART_SDK_DIR = os.path.join(THIS_DIR, 'dart-sdk')
-STAMP_FILE = os.path.join(DART_SDK_DIR, 'STAMP_FILE')
-LIBRARIES_FILE = os.path.join(DART_SDK_DIR,'dart-sdk',
-                              'lib', '_internal', 'libraries.dart')
-
-def RunCommand(command, fail_hard=True):
-  """Run command and return success (True) or failure; or if fail_hard is
-     True, exit on failure."""
-
-  print 'Running %s' % (str(command))
-  if subprocess.call(command, shell=False) == 0:
-    return True
-  print 'Failed.'
-  if fail_hard:
-    sys.exit(1)
-  return False
-
-def main():
-  # Only get the SDK if we don't have a stamp for or have an out of date stamp
-  # file.
-  get_sdk = False
-  if sys.platform.startswith('linux'):
-    sdk_url = SDK_URL_BASE + LINUX_64_SDK
-    output_file = os.path.join(DART_SDK_DIR, LINUX_64_SDK)
-  elif sys.platform.startswith('darwin'):
-    sdk_url = SDK_URL_BASE + MACOS_64_SDK
-    output_file = os.path.join(DART_SDK_DIR, MACOS_64_SDK)
-  else:
-    print "Platform not supported"
-    return 1
-
-  if not os.path.exists(STAMP_FILE):
-    get_sdk = True
-  else:
-    # Get the contents of the stamp file.
-    with open(STAMP_FILE, "r") as stamp_file:
-      stamp_url = stamp_file.read().replace('\n', '')
-      if stamp_url != sdk_url:
-        get_sdk = True
-
-  if get_sdk:
-    # Completely remove all traces of the previous SDK.
-    if os.path.exists(DART_SDK_DIR):
-      shutil.rmtree(DART_SDK_DIR)
-    os.mkdir(DART_SDK_DIR)
-
-    # Download the Linux x64 based Dart SDK.
-    # '-C -': Resume transfer if possible.
-    # '--location': Follow Location: redirects.
-    # '-o': Output file.
-    curl_command = ['curl',
-                    '-C', '-',
-                    '--location',
-                    '-o', output_file,
-                    sdk_url]
-    if not RunCommand(curl_command, fail_hard=False):
-      print "Failed to get dart sdk from server."
-      return 1
-
-    # Write our stamp file so we don't redownload the sdk.
-    with open(STAMP_FILE, "w") as stamp_file:
-      stamp_file.write(sdk_url)
-
-  unzip_command = ['unzip', '-o', '-q', output_file, '-d', DART_SDK_DIR]
-  if not RunCommand(unzip_command, fail_hard=False):
-    print "Failed to unzip the dart sdk."
-    return 1
-
-  return 0
-
-if __name__ == '__main__':
-  sys.exit(main())