GN: get Angle compiling on Windows.

Angle does not yet link, but it does compile.

I chickened out and wrote cp.py to be the copy tool on Windows.  I've got all platforms using it for consistency.


CQ_INCLUDE_TRYBOTS=master.client.skia.compile:Build-Ubuntu-GCC-x86_64-Release-ANGLE-Trybot


GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3533

Change-Id: I15f4b63a47121528b2fd2672c26c62765966147c
Reviewed-on: https://skia-review.googlesource.com/3533
Reviewed-by: Mike Klein <mtklein@chromium.org>
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
diff --git a/gn/cp.py b/gn/cp.py
new file mode 100644
index 0000000..eedfcb2
--- /dev/null
+++ b/gn/cp.py
@@ -0,0 +1,23 @@
+#!/usr/bin/env python
+#
+# Copyright 2016 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os
+import shutil
+import sys
+
+src, dst = sys.argv[1:]
+
+if os.path.exists(dst):
+  if os.path.isdir(dst):
+    shutil.rmtree(dst)
+  else:
+    os.remove(dst)
+
+if os.path.isdir(src):
+  shutil.copytree(src, dst)
+else:
+  shutil.copy2(src, dst)