Add Platform Independent Eddystone Encoder

components/physical_web/eddystone/BUILD.gn

Index: components/physical_web/eddystone/BUILD.gn
diff --git a/components/physical_web/eddystone/BUILD.gn b/components/physical_web/eddystone/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..a77baaaa240860a46f57993660418a714a501aad
--- /dev/null
+++ b/components/physical_web/eddystone/BUILD.gn
@@ -0,0 +1,27 @@
+# Copyright 2017 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.
+
+source_set("eddystone") {
+  sources = [
+    "eddystone_encoder.cc",
+    "eddystone_encoder.h",
+  ]
+
+  deps = [
+    "//url",
+  ]
+}
+
+source_set("unit_tests") {
+  testonly = true
+  sources = [
+    "eddystone_encoder_unittest.cc",
+  ]
+
+  deps = [
+    ":eddystone",
+    "//testing/gtest",
+    "//url",
+  ]
+}