Add the "testonly" flag to the GN test target.

build/config/android/rules.gni

 # Copyright 2014 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/config.gni")
 import("//build/config/android/internal_rules.gni")
 import("//tools/grit/grit_rule.gni")
 
 assert(is_android)
 
@@ skipping 557 matching lines @@
 #     (and so not through builtin targets like 'action', 'group', etc).
 #   java_files: List of .java files to include in the apk.
 #   srcjar_deps: List of srcjar dependencies. The .java files in the srcjars
 #      will be added to java_files and be included in this apk.
 #   apk_name: Name for final apk.
 #   final_apk_path: Path to final built apk. Default is
 #     $root_out_dir/apks/$apk_name.apk. Setting this will override apk_name.
 #   native_libs: List paths of native libraries to include in this apk. If these
 #     libraries depend on other shared_library targets, those dependencies will
 #     also be included in the apk.
+#   testonly: Marks this target as "test-only".
 #
 #   DEPRECATED_java_in_dir: Directory containing java files. All .java files in
 #     this directory will be included in the library. This is only supported to
 #     ease the gyp->gn conversion and will be removed in the future.
 #
 # Example
 #   android_apk("foo_apk") {
 #     android_manifest = "AndroidManifest.xml"
 #     java_files = [
 #       "android/org/chromium/foo/FooApplication.java",
@@ skipping 52 matching lines @@
 
   write_build_config("${target_name}__build_config") {
     type = "android_apk"
     srcjar = resource_srcjar_path
     dex_path = final_dex_path
     resources_zip = resources_zip_path
 
     if (defined(invoker.deps)) {
       deps = invoker.deps
     }
+    if (defined(invoker.testonly)) {
+      testonly = invoker.testonly
+    }
 
     native_libs = _native_libs
   }
 
   final_deps = []
 
   final_deps += [":${target_name}__process_resources"]
   process_resources("${target_name}__process_resources") {
     android_manifest = invoker.android_manifest
 
@@ skipping 134 matching lines @@
     final_apk_path = "$root_build_dir/${apk_name}_apk/${apk_name}-debug.apk"
     java_files = [
       "//testing/android/java/src/org/chromium/native_test/ChromeNativeTestActivity.java"
     ]
     android_manifest = "//testing/android/java/AndroidManifest.xml"
     unittests_outputs = [ unittests_binary ]
     native_libs = [unittests_outputs[0]]
     if (defined(invoker.deps)) {
       deps = invoker.deps
     }
+    testonly = true
   }
 }
 
 # Generate .java files from .aidl files.
 #
 # This target will store the .java files in a srcjar and should be included in
 # an android_library or android_apk's srcjar_deps.
 #
 # Variables
 #   sources: Paths to .aidl files to compile.
@@ skipping 52 matching lines @@
           "//build/android/gyp/find.py",
           rebase_path([invoker.import_include], root_build_dir),
           "list lines"
           )
       _java_files = rebase_path(_java_files_build_rel, ".", root_build_dir)
       inputs += _java_files
     }
     args += rebase_path(sources, root_build_dir)
   }
 }