[headless] Remove default browser context.

headless/lib/browser/headless_browser_main_parts.cc

Index: headless/lib/browser/headless_browser_main_parts.cc
diff --git a/headless/lib/browser/headless_browser_main_parts.cc b/headless/lib/browser/headless_browser_main_parts.cc
index c970b7907392e9329ec43a8c69f4cf846ea9f149..a551a8be33d64c9c49744773d1987a150e47619b 100644
--- a/headless/lib/browser/headless_browser_main_parts.cc
+++ b/headless/lib/browser/headless_browser_main_parts.cc
@@ -5,9 +5,11 @@
 #include "headless/lib/browser/headless_browser_main_parts.h"
 
 #include "components/devtools_http_handler/devtools_http_handler.h"
+#include "content/public/browser/browser_thread.h"
 #include "headless/lib/browser/headless_browser_context_impl.h"
 #include "headless/lib/browser/headless_browser_impl.h"
 #include "headless/lib/browser/headless_devtools.h"
+#include "headless/lib/browser/headless_devtools_manager_delegate.h"
 #include "headless/lib/browser/headless_screen.h"
 #include "ui/aura/env.h"
 #include "ui/display/screen.h"
@@ -32,24 +34,19 @@ HeadlessBrowserMainParts::HeadlessBrowserMainParts(HeadlessBrowserImpl* browser)
 HeadlessBrowserMainParts::~HeadlessBrowserMainParts() {}
 
 void HeadlessBrowserMainParts::PreMainMessageLoopRun() {
-  browser_context_.reset(new HeadlessBrowserContextImpl(ProtocolHandlerMap(),
-                                                        browser_->options()));
   if (browser_->options()->devtools_endpoint.address().IsValid()) {
     devtools_http_handler_ =
-        CreateLocalDevToolsHttpHandler(browser_context_.get());
+        CreateLocalDevToolsHttpHandler(browser_->options());
   }
   PlatformInitialize();
 }
 
 void HeadlessBrowserMainParts::PostMainMessageLoopRun() {
-  browser_context_.reset();
+  DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+
   devtools_http_handler_.reset();
-  PlatformExit();
-}
 
-HeadlessBrowserContextImpl* HeadlessBrowserMainParts::default_browser_context()
-    const {
-  return browser_context_.get();
+  PlatformExit();
 }
 
 }  // namespace headless