Update from https://crrev.com/312398

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 2f8abdde615119b56010815e19e4d34cd0015d1d..b31535e8d887f4420289835294f000edbbe4e7d7 100644
--- a/mojo/edk/system/BUILD.gn
+++ b/mojo/edk/system/BUILD.gn
@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import("../mojo_edk.gni")
+import("//testing/test.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
@@ -198,12 +199,3 @@ 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"
-  }
-}