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/osr/software_output_device_osr.h

@@ -7,7 +7,6 @@
 #define CEF_LIBCEF_BROWSER_OSR_SOFTWARE_OUTPUT_DEVICE_OSR_H_
 
 #include "base/callback.h"
-#include "base/memory/scoped_ptr.h"
 #include "cc/output/software_output_device.h"
 
 namespace ui {
@@ -45,8 +44,8 @@ class CefSoftwareOutputDeviceOSR : public cc::SoftwareOutputDevice {
   const OnPaintCallback callback_;
 
   bool active_;
-  scoped_ptr<SkCanvas> canvas_;
-  scoped_ptr<SkBitmap> bitmap_;
+  std::unique_ptr<SkCanvas> canvas_;
+  std::unique_ptr<SkBitmap> bitmap_;
   gfx::Rect pending_damage_rect_;
 
   DISALLOW_COPY_AND_ASSIGN(CefSoftwareOutputDeviceOSR);