convert //headless to std::unique_ptr

headless/lib/headless_content_main_delegate.cc

Index: headless/lib/headless_content_main_delegate.cc
diff --git a/headless/lib/headless_content_main_delegate.cc b/headless/lib/headless_content_main_delegate.cc
index 64e91c0930230d38aa3b7b16aa3475d4f207ab9f..245341fcb43362d8ea6fbc222e2311b8b94c8ea7 100644
--- a/headless/lib/headless_content_main_delegate.cc
+++ b/headless/lib/headless_content_main_delegate.cc
@@ -27,7 +27,7 @@ HeadlessContentMainDelegate* g_current_headless_content_main_delegate = nullptr;
 }  // namespace
 
 HeadlessContentMainDelegate::HeadlessContentMainDelegate(
-    scoped_ptr<HeadlessBrowserImpl> browser)
+    std::unique_ptr<HeadlessBrowserImpl> browser)
     : content_client_(browser->options()), browser_(std::move(browser)) {
   DCHECK(!g_current_headless_content_main_delegate);
   g_current_headless_content_main_delegate = this;
@@ -69,7 +69,7 @@ int HeadlessContentMainDelegate::RunProcess(
   base::trace_event::TraceLog::GetInstance()->SetProcessSortIndex(
       kTraceEventBrowserProcessSortIndex);
 
-  scoped_ptr<content::BrowserMainRunner> browser_runner(
+  std::unique_ptr<content::BrowserMainRunner> browser_runner(
       content::BrowserMainRunner::Create());
 
   int exit_code = browser_runner->Initialize(main_function_params);