A little bit of strict-mode in my life.

lighthouse-core/scripts/build-traceviewer-module.js

@@ -45,7 +45,7 @@ function convertImport(src) {
       const imports = window.document.querySelectorAll('link[rel="import"]');
       const scripts = window.document.querySelectorAll('script');
       let scriptsContent = '';
-
+      scriptsContent += addUseStrictDirective();
       scriptsContent += convertLicenseComments(html);
 
       // traverse and rewrite the imports
@@ -110,6 +110,11 @@ function convertImport(src) {
         return script;
       }
 
+      // the "use strict" must be found *above* the require() statements
+      function addUseStrictDirective() {
+        return '"use strict";\n';
+      }
+
       function writeNewFile(dest, scriptsContent) {
         dest = dest.replace('./third_party/src/catapult/tracing/tracing/', '');
         dest = path.resolve('./third_party/traceviewer-js/' + dest);

lighthouse-core/third_party/traceviewer-js/base/base.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/base64.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/category_util.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/color.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/color_scheme.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/event.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/event_target.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/extension_registry.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/extension_registry_base.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/extension_registry_basic.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/extension_registry_type_based.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/guid.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/interval_tree.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/iteration_helpers.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/math.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/multi_dimensional_view.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/piecewise_linear_function.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/quad.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/raf.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/range.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/range_utils.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/rect.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/running_statistics.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/sinebow_color_generator.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/sorted_array_utils.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/statistics.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/task.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/time_display_modes.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/timing.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/unit.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/unit_scale.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/base/utils.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/core/auditor.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/core/filter.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2012 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/chrome/cc/input_latency_async_slice.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/chrome/chrome_user_friendly_category_driver.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/importer/trace_code_entry.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/importer/trace_code_map.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/importer/trace_event_importer.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2012 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/importer/v8/codemap.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2012 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/importer/v8/splaytree.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2012 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/extras/lean_config.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/context_processor.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/empty_importer.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/find_input_expectations.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/find_load_expectations.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/find_startup_expectations.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/import.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/importer.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2013 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/proto_expectation.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/importer/user_model_builder.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/index.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/all_metrics.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/blink/gc_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/cpu_process_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/metric_registry.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/sample_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/clock_sync_latency_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/cpu_time_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/hazard_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/loading_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/long_tasks_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/memory_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/power_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/responsiveness_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/system_health_metrics.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/utils.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/system_health/webview_startup_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/tracing_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/v8/execution_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/v8/gc_metric.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/v8/utils.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/metrics/v8/v8_metrics.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright 2016 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/model/alert.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be

lighthouse-core/third_party/traceviewer-js/model/annotation.js

@@ -1,3 +1,4 @@
+"use strict";
 /**
 Copyright (c) 2015 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be