Various fixes related to the C++11/14 update (see issue #3140)

- Convert scoped_ptr to std::unique_ptr from <memory>
- Convert arraysize to base::size from include/base/cef_cxx17_backports.h
- Convert NULL to nullptr
- Include include/base/cef_callback.h instead of include/base/cef_bind.h
- Implicit conversion of CefRefPtr<T> or scoped_refptr<T> to T* is gone;
  use .get() instead

See the issue for additional details.

tests/cefclient/browser/osr_render_handler_win_gl.cc

@@ -4,7 +4,7 @@
 
 #include "tests/cefclient/browser/osr_render_handler_win_gl.h"
 
-#include "include/base/cef_bind.h"
+#include "include/base/cef_callback.h"
 #include "include/wrapper/cef_closure_task.h"
 #include "include/wrapper/cef_helpers.h"
 #include "tests/shared/browser/util_win.h"
@@ -23,7 +23,7 @@ class ScopedGLContext {
     DCHECK(result);
   }
   ~ScopedGLContext() {
-    BOOL result = wglMakeCurrent(NULL, NULL);
+    BOOL result = wglMakeCurrent(nullptr, nullptr);
     DCHECK(result);
     if (swap_buffers_) {
       result = SwapBuffers(hdc_);
@@ -43,8 +43,8 @@ OsrRenderHandlerWinGL::OsrRenderHandlerWinGL(
     HWND hwnd)
     : OsrRenderHandlerWin(settings, hwnd),
       renderer_(settings),
-      hdc_(NULL),
-      hrc_(NULL),
+      hdc_(nullptr),
+      hrc_(nullptr),
       painting_popup_(false) {}
 
 void OsrRenderHandlerWinGL::Initialize(CefRefPtr<CefBrowser> browser) {
@@ -194,8 +194,8 @@ void OsrRenderHandlerWinGL::DisableGL() {
     ReleaseDC(hwnd(), hdc_);
   }
 
-  hdc_ = NULL;
-  hrc_ = NULL;
+  hdc_ = nullptr;
+  hrc_ = nullptr;
 }
 
 }  // namespace client