Update to Chromium revision 6e53600d (#386251)

- Remove |accept_lang| parameter from CefJSDialogHandler::OnJSDialog
  and CefFormatUrlForSecurityDisplay (see https://crbug.com/336973#c36).
- Remove remaining NPAPI-related code including functions from
  cef_web_plugin.h (see https://crbug.com/493212#c55).
- Mac: 10.7+ deployment target is now required for client applications.
- Mac: Remove CefBrowserHost::SetWindowVisibility (issue #1375). No
  replacement is required for windowed rendering. Use WasHidden for
  off-screen rendering.
- Windows: Visual Studio 2015 Update 2 is now required when building
  CEF/Chromium.

libcef/browser/component_updater/cef_component_updater_configurator.cc

@@ -92,7 +92,7 @@ std::string GetSwitchArgument(const std::vector<std::string>& vec,
 class CefConfigurator : public Configurator {
  public:
   CefConfigurator(const base::CommandLine* cmdline,
-                     net::URLRequestContextGetter* url_request_getter);
+                  net::URLRequestContextGetter* url_request_getter);
 
   int InitialDelay() const override;
   int NextCheckDelay() const override;
@@ -103,6 +103,7 @@ class CefConfigurator : public Configurator {
   std::vector<GURL> PingUrl() const override;
   base::Version GetBrowserVersion() const override;
   std::string GetChannel() const override;
+  std::string GetBrand() const override;
   std::string GetLang() const override;
   std::string GetOSLongName() const override;
   std::string ExtraRequestParams() const override;
@@ -214,6 +215,10 @@ std::string CefConfigurator::GetChannel() const {
   return "";
 }
 
+std::string CefConfigurator::GetBrand() const {
+  return "";
+}
+
 std::string CefConfigurator::GetLang() const {
   return "";
 }