Add BUILD.gn files for chromecast/media

chromecast/BUILD.gn

Index: chromecast/BUILD.gn
diff --git a/chromecast/BUILD.gn b/chromecast/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..6169cf8680863712ea2ad348fdd5d7cbe8074a85
--- /dev/null
+++ b/chromecast/BUILD.gn
@@ -0,0 +1,21 @@
+# 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.
+
+import("//chromecast/chromecast.gni")
+
+config("config") {
+  defines = []
+
+  if (use_playready) {
+    defines += [ "PLAYREADY_CDM_AVAILABLE" ]
+  }
+}
+
+component("chromecast") {
+  deps = [
+    "//chromecast/base",
+    "//chromecast/base/metrics",
+    "//chromecast/media",
+  ]
+}