Update to Chromium version 86.0.4240.0 (#800218)

- CefURLRequest::Create is no longer supported in the renderer process
  (see https://crbug.com/891872). Use CefFrame::CreateURLRequest instead.
- Mac platform definitions have been changed from `MACOSX` to `MAC`
  (see https://crbug.com/1105907) and related CMake macro names have
  been updated. The old `OS_MACOSX` define is still set in code and CMake
  for backwards compatibility.
- Linux ARM build is currently broken (see https://crbug.com/1123214).

libcef/browser/chrome/chrome_content_browser_client_cef.cc

@@ -26,7 +26,8 @@ ChromeContentBrowserClientCef::CreateBrowserMainParts(
       ChromeContentBrowserClient::CreateBrowserMainParts(parameters);
   browser_main_parts_ = new ChromeBrowserMainExtraPartsCef;
   static_cast<ChromeBrowserMainParts*>(main_parts.get())
-      ->AddParts(browser_main_parts_);
+      ->AddParts(
+          base::WrapUnique<ChromeBrowserMainExtraParts>(browser_main_parts_));
   return main_parts;
 }