Add infrastructure to run tests on android.

mojo/edk/system/BUILD.gn

Index: mojo/edk/system/BUILD.gn
diff --git a/mojo/edk/system/BUILD.gn b/mojo/edk/system/BUILD.gn
index b87c76ad490b9d68923af9de37d9eb5003c43d6c..0701484b3441737dc22dadd6450789c023674c27 100644
--- a/mojo/edk/system/BUILD.gn
+++ b/mojo/edk/system/BUILD.gn
@@ -2,6 +2,11 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+if (is_android) {
+  import("//build/config/android/config.gni")
+  import("//build/config/android/rules.gni")
+}
+
 config("system_config") {
   defines = [
     # Ensures that dependent projects import the core functions on Windows.
@@ -143,6 +148,12 @@ test("mojo_system_unittests") {
     "//testing/gtest",
   ]
 
+  if (is_android) {
+    deps += [
+      "//testing/android:native_test_native_code",
+    ]
+  }
+
   allow_circular_includes_from = [ "//mojo/edk/embedder:embedder_unittests" ]
 }
 
@@ -165,3 +176,12 @@ test("mojo_message_pipe_perftests") {
     "//testing/gtest",
   ]
 }
+
+if (is_android) {
+  unittest_apk("mojo_system_unittests_apk") {
+    deps = [
+      ":mojo_system_unittests",
+    ]
+    unittests_dep = ":mojo_system_unittests"
+  }
+}