android: Convert java_deobfuscate.py to Java

third_party/proguard/BUILD.gn

Index: third_party/proguard/BUILD.gn
diff --git a/third_party/proguard/BUILD.gn b/third_party/proguard/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..0a5e2441736ca176a241493c4a5fd0e67ac966de
--- /dev/null
+++ b/third_party/proguard/BUILD.gn
@@ -0,0 +1,16 @@
+# 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.
+
+import("//build/config/android/rules.gni")
+
+java_prebuilt("proguard_java") {
+  jar_path = "lib/proguard.jar"
+}
+
+java_prebuilt("retrace_java") {
+  jar_path = "lib/retrace.jar"
+  deps = [
+    ":proguard_java",
+  ]
+}