Add more tracing to Sky

sky/engine/core/script/dart_controller.cc

 // 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.
 
 #include "sky/engine/config.h"
 #include "sky/engine/core/script/dart_controller.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/single_thread_task_runner.h"
+#include "base/trace_event/trace_event.h"
 #include "dart/runtime/include/dart_mirrors_api.h"
 #include "sky/engine/bindings/builtin.h"
 #include "sky/engine/bindings/builtin_natives.h"
 #include "sky/engine/bindings/builtin_sky.h"
 #include "sky/engine/core/app/AbstractModule.h"
 #include "sky/engine/core/app/Module.h"
 #include "sky/engine/core/dom/Element.h"
 #include "sky/engine/core/frame/LocalFrame.h"
 #include "sky/engine/core/html/HTMLScriptElement.h"
 #include "sky/engine/core/html/imports/HTMLImport.h"
@@ skipping 99 matching lines @@
   // TODO(eseidel): Better if the library/module retained its dependencies and
   // dependency waiting could be separate from library creation.
   dart_state()->loader().WaitForDependencies(
       dependency_catcher.dependencies(),
       base::Bind(finished_callback, module, library));
 }
 
 void DartController::ExecuteLibraryInModule(AbstractModule* module,
                                             Dart_Handle library,
                                             HTMLScriptElement* script) {
+  TRACE_EVENT1("sky", "DartController::ExecuteLibraryInModule",
+               "url", module->url().ascii().toStdString());
   ASSERT(library);
   DCHECK(Dart_CurrentIsolate() == dart_state()->isolate());
   DartApiScope dart_api_scope;
 
   // Don't continue if we failed to load the module.
   if (LogIfError(Dart_FinalizeLoading(true)))
     return;
   const char* name = module->isApplication() ? "main" : "_init";
 
   // main() is required, but init() is not:
@@ skipping 160 matching lines @@
 
   CHECK(Dart_SetVMFlags(argc, argv));
   CHECK(Dart_Initialize(IsolateCreateCallback,
                         nullptr,  // Isolate interrupt callback.
                         UnhandledExceptionCallback, IsolateShutdownCallback,
                         // File IO callbacks.
                         nullptr, nullptr, nullptr, nullptr, nullptr));
 }
 
 } // namespace blink