[Startup Tracing] Add --trace-config-file flag

components/components_tests.gyp

Index: components/components_tests.gyp
diff --git a/components/components_tests.gyp b/components/components_tests.gyp
index 4e4a6bc4fb441b9b3cbabe170fba0c520ac4f963..1a586528be005125b1f8c53daba155b701705508 100644
--- a/components/components_tests.gyp
+++ b/components/components_tests.gyp
@@ -609,6 +609,9 @@
       'sync_driver/tab_node_pool_unittest.cc',
       'sync_driver/ui_data_type_controller_unittest.cc',
     ],
+    'tracing_unittest_sources': [
+      'tracing/trace_config_file_unittest.cc',
+    ],
     'translate_unittest_sources': [
       'translate/core/browser/language_state_unittest.cc',
       'translate/core/browser/translate_browser_metrics_unittest.cc',
@@ -1152,6 +1155,10 @@
         ['OS != "android"', {
           'sources': [
             '<@(invalidation_unittest_sources)',
+            '<@(tracing_unittest_sources)',
+          ],
+          'dependencies': [
+            'tracing.gyp:tracing',
           ],
         }],
         ['OS != "ios" and OS != "android"', {