Add callback to allow Document PiP moveTo/By() (fixes #3714)

Allow Document picture-in-picture moveTo/By() and resizeTo/By()
(without user gesture) if the new
CefBrowserViewDelegate::AllowMoveForPictureInPicture callback
returns true.

include/views/cef_browser_view_delegate.h

@@ -38,6 +38,7 @@
 #define CEF_INCLUDE_VIEWS_CEF_BROWSER_VIEW_DELEGATE_H_
 #pragma once
 
+#include "include/cef_api_hash.h"
 #include "include/cef_client.h"
 #include "include/views/cef_view_delegate.h"
 
@@ -129,6 +130,18 @@ class CefBrowserViewDelegate : public CefViewDelegate {
     return false;
   }
 
+#if CEF_API_ADDED(CEF_NEXT)
+  ///
+  /// Return true to allow the use of JavaScript moveTo/By() and resizeTo/By()
+  /// (without user activation) with Document picture-in-picture popups.
+  ///
+  /*--cef(added=next)--*/
+  virtual bool AllowMoveForPictureInPicture(
+      CefRefPtr<CefBrowserView> browser_view) {
+    return false;
+  }
+#endif
+
   ///
   /// Called when |browser_view| receives a gesture command. Return true to
   /// handle (or disable) a |gesture_command| or false to propagate the gesture