Add a script to sky pub package to download assets

sky/sdk/packages/sky/lib/download_material_design_icons

Index: sky/sdk/packages/sky/lib/download_material_design_icons
diff --git a/sky/tools/download_material_design_icons b/sky/sdk/packages/sky/lib/download_material_design_icons
similarity index 55%
copy from sky/tools/download_material_design_icons
copy to sky/sdk/packages/sky/lib/download_material_design_icons
index fd08a1dd34ac7f197e1a4bee3215e3068ded9df6..6087c48fb89e9c15ebe598d9f5393fd259ed7517 100755
--- a/sky/tools/download_material_design_icons
+++ b/sky/sdk/packages/sky/lib/download_material_design_icons
@@ -5,27 +5,21 @@
 
 import os
 import subprocess
+import urllib2
 
-from webkitpy.common.system import filesystem
-from webkitpy.common.webkit_finder import WebKitFinder
-
-finder = WebKitFinder(filesystem.FileSystem())
-
-assets_dir = finder.path_from_chromium_base('sky', 'assets')
+sky_lib_dir = os.path.dirname(os.path.abspath(__file__))
+assets_dir = os.path.join(sky_lib_dir, 'assets')
 sha1_path = os.path.join(assets_dir, 'material-design-icons.sha1')
 
-with open(sha1_path) as f:
+with open(sha1_path, 'r') as f:
     sha1 = f.read()
 
 tgz_path = os.path.join(assets_dir, 'material-design-icons.tgz')
-subprocess.call([
-    'download_from_google_storage',
-    '--no_resume',
-    '--no_auth',
-    '--bucket', 'mojo',
-    '--output', tgz_path,
-    'material-design-icons/%s' % sha1,
-])
+url = 'https://storage.googleapis.com/mojo/material-design-icons/%s' % sha1
+response = urllib2.urlopen(url)
+
+with open(tgz_path, 'wb') as f:
+    f.write(response.read())
 
 output_path = os.path.join(assets_dir, tgz_path)
 subprocess.call([