[WIP] Adding Mockito support in Android instrumentation tests

third_party/android_dalvik_dx/BUILD.gn

Index: third_party/android_dalvik_dx/BUILD.gn
diff --git a/third_party/android_dalvik_dx/BUILD.gn b/third_party/android_dalvik_dx/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..61a87b77588cde2a7fab89c5d2509ca459dc72e6
--- /dev/null
+++ b/third_party/android_dalvik_dx/BUILD.gn
@@ -0,0 +1,13 @@
+# 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")
+
+android_java_prebuilt("android_dalvik_dx_java") {
+  testonly = true
+  jar_path = "lib/dalvik-dx-7.1.0_r7.jar"
+  deps = [
+    "//third_party/android_libcore_dex:android_libcore_dex_java",
+  ]
+}