[Android] Generate scripts at build time to run android tests.

build/android/test_runner.gypi

+# Copyright 2015 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.
+
+# Generates a script in the output bin directory which runs the test
+# target using the test runner script in build/android/pylib/test_runner.py.
+#
+# To use this, include this file in a gtest or instrumentation test target.
+# {
+#   'target_name': 'gtest',
+#   'type': 'none',
+#   'variables': {
+#     'test_type': 'gtest',  # string
+#     'test_suite_name': 'gtest_suite'  # string
+#     'isolate_file': 'path/to/gtest.isolate'  # string
+#   },
+#   'includes': ['path/to/this/gypi/file'],
+# }
+#
+# {
+#   'target_name': 'instrumentation_apk',
+#   'type': 'none',
+#   'variables': {
+#     'test_type': 'instrumentation',  # string
+#     'apk_name': 'TestApk'  # string
+#     'isolate_file': 'path/to/instrumentation_test.isolate'  # string
+#   },
+#   'includes': ['path/to/this/gypi/file'],
+# }
+#
+
+{
+  'variables': {
+    'variables': {
+      'isolate_file%': '',
+    },
+    'test_runner_args': ['--output-directory', '<(PRODUCT_DIR)'],
+    'conditions': [
+      ['test_type == "gtest"', {
+        'test_runner_args': ['--suite', '<(test_suite_name)'],
+        'script_name': 'run_<(test_suite_name)',
+      }],
+      ['test_type == "instrumentation"', {
+        'test_runner_args': ['--test-apk', '<(apk_name)'],
+        'script_name': 'run_<(_target_name)',
+      }],
+      ['isolate_file != ""', {
+        'test_runner_args': ['--isolate-file-path', '<(isolate_file)']
+      }],
+    ],
+  },
+  'actions': [
+    {
+      'action_name': 'create_test_runner_script_<(script_name)',
+      'message': 'Creating test runner script <(script_name)',
+      'variables': {
+        'script_output_path': '<(PRODUCT_DIR)/bin/<(script_name)',
+      },
+      'inputs': [
+        '<(DEPTH)/build/android/gyp/create_test_runner_script.py',
+      ],
+      'outputs': [
+        '<(script_output_path)'
+      ],
+      'action': [
+        'python', '<(DEPTH)/build/android/gyp/create_test_runner_script.py',
+        '--script-output-path=<(script_output_path)',
+        '<(test_type)', '<@(test_runner_args)',
+      ],
+    },
+  ],
+}