Move third_party/WebCore to git

DEPS

 # 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.
 
 vars = {
   # The dart_root is the root of our sdk checkout. This is normally
   # simply sdk, but if using special gclient specs it can be different.
   "dart_root": "sdk",
 
   # The svn location to pull out dependencies from
@@ skipping 78 matching lines @@
   "sunflower_rev": "@879b704933413414679396b129f5dfa96f7a0b1e",
   "test_tag": "@0.12.6+1",
   "test_reflective_loader_tag": "@0.0.3",
   "utf_rev": "@1f55027068759e2d52f2c12de6a57cce5f3c5ee6",
   "unittest_tag": "@0.11.6",
   "usage_rev": "@b5080dac0d26a5609b266f8fdb0d053bc4c1c638",
   "watcher_tag": "@0.9.7",
   "when_tag": "@0.2.0+2",
   "which_tag": "@0.1.3+1",
   "web_components_rev": "@0e636b534d9b12c9e96f841e6679398e91a986ec",
-  "WebCore_rev" : "@44061",
+  "WebCore_rev": "@4f90b41b0165f23f412cecdba07b7d81d3fbb5b5",
   "yaml_tag": "@2.1.5",
   "zlib_rev": "@c3d0a6190f2f8c924a05ab6cc97b8f975bddd33f",
   "barback-0.13.0_rev": "@34853",
   "barback-0.14.0_rev": "@36398",
   "barback-0.14.1_rev": "@38525",
   "source_maps-0.9.4_rev": "@38524",
 }
 
 deps = {
   # Stuff needed for GYP to run.
@@ skipping 21 matching lines @@
 
   Var("dart_root") + "/third_party/ply":
       Var("chromium_git") + "/chromium/src/third_party/ply.git" +
       Var("ply_rev"),
 
   Var("dart_root") + "/third_party/idl_parser":
       Var("chromium_git") + "/chromium/src/tools/idl_parser.git" +
       Var("idl_parser_rev"),
 
   Var("dart_root") + "/third_party/WebCore":
-      Var("third_party") + "/WebCore" + Var("WebCore_rev"),
+      "https://github.com/dart-lang/webcore.git" + Var("WebCore_rev"),
 
   Var("dart_root") + "/third_party/pkg/args":
       (Var("github_mirror") % "args") + Var("args_tag"),
   Var("dart_root") + "/third_party/pkg/async":
       (Var("github_mirror") % "async") + Var("async_tag"),
   Var("dart_root") + "/third_party/pkg/barback":
       (Var("github_mirror") % "barback") + Var("barback_tag"),
   Var("dart_root") + "/third_party/pkg/charcode":
       (Var("github_mirror") % "charcode") + Var("charcode_tag"),
   Var("dart_root") + "/third_party/pkg/cli_util":
@@ skipping 262 matching lines @@
       "--no_auth",
       "--no_resume",
       "--bucket",
       "dart-dependencies",
       "--extract",
       "-s",
       Var('dart_root') + "/third_party/gsutil.tar.gz.sha1",
     ],
   },
 ]