[code coverage] Forward use_clang_coverage arg to iOS test runner scripts.

This change will forward the build arg to iOS test runner scripts. CL
changing how test runner scripts are consuming this arg is at
crrev/c/2092941.

Bug: 943883
Change-Id: I4f52cf5fcc83cdca75570c812fd1c0629a96f4ff
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2099479Reviewed-by: John Budorick <jbudorick@chromium.org>
Reviewed-by: Sylvain Defresne <sdefresne@chromium.org>
Commit-Queue: Zhaoyang Li <zhaoyangli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#749729}

build/config/ios/ios_test_runner_wrapper.gni

@@ -2,6 +2,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/config/coverage/coverage.gni")
 import("//build/config/ios/ios_sdk.gni")
 import("//build/config/ios/ios_test_runner_config.gni")
 import("//build/util/generate_wrapper.gni")
@@ -93,6 +94,10 @@ template("ios_test_runner_wrapper") {
       "${shards}",
     ]
 
+    if (use_clang_coverage) {
+      executable_args += [ "--use-clang-coverage" ]
+    }
+
     # test runner relies on iossim if use_ios_simulator (defined in ios_sdk.gni)
     if (use_ios_simulator) {
       _rebased_root_build_dir = rebase_path("${root_build_dir}", root_build_dir)

ios/build/bots/scripts/run.py

@@ -349,6 +349,11 @@ class Runner():
               'will be excluded from this run. If unspecified, run all tests.'),
         metavar='testcase',
     )
+    parser.add_argument(
+        '--use-clang-coverage',
+        help='Enable code coverage related steps in test runner scripts.',
+        action='store_true',
+    )
     parser.add_argument(
         '--use-trusted-cert',
         action='store_true',
@@ -405,7 +410,6 @@ class Runner():
       args.restart = args_json.get('restart', args.restart)
       args.test_cases = args.test_cases or []
       args.test_cases.extend(args_json.get('test_cases', []))
-      args.use_clang_coverage = args_json.get('use_clang_coverage', False)
       args.xctest = args_json.get('xctest', args.xctest)
       args.xcode_parallelization = args_json.get('xcode_parallelization',
                                                  args.xcode_parallelization)