feat: add new option for devtools xwidgets support

Allows the use of flutter devtools within an xwidgets frame

Author: elken

README.md

@@ -150,6 +150,19 @@ matching names.
 
 You can also open the [Dart DevTools](https://dart.dev/tools/dart-devtools) on the current debug session with `lsp-dart-open-devtools`.
 
+It's also possible to spawn the devtools inside an
+[XWidgets](https://www.emacswiki.org/emacs/EmacsXWidgets) frame by enabling
+`lsp-dart-devtools-prefer-xwidgets` and ensuring that your emacs has proper
+support for xwidgets frames.
+
+NVIDIA users may have to enable the below environment variables:
+
+``` shell
+WEBKIT_DISABLE_COMPOSITING_MODE=1
+WEBKIT_FORCE_SANDBOX=0
+```
+
+
 ### Commands
 
 lsp-dart supports running Flutter and Dart commands as following:

lsp-dart-devtools.el

@@ -37,6 +37,13 @@
   :group 'lsp-dart
   :type 'string)
 
+(defcustom lsp-dart-devtools-prefer-xwidgets nil
+  "If t and xwidgets support exists, open the devtools in an xwidget-webkit
+  view.
+NOTE XWidgets are still quite buggy so only enable this if you know you have support"
+  :group 'lsp-dart
+  :type 'boolean)
+
 (defconst lsp-dart-devtools--buffer-name "*LSP Dart - DevTools*")
 
 (defun lsp-dart-devtools-log (msg &rest args)
@@ -133,7 +140,12 @@ If it is already activated or after activated successfully, call CALLBACK."
                                            (hide ,lsp-dart-devtools-hide-options)
                                            (theme ,lsp-dart-devtools-theme))))
          (url (concat "http://" uri "?" params)))
-    (browse-url url)))
+    (if (and lsp-dart-devtools-prefer-xwidgets
+             (featurep 'xwidget-internal))
+        (progn
+          (select-window (split-window (selected-window) nil 'right))
+          (xwidget-webkit-browse-url url))
+      (browse-url url))))
 
 
 ;;; Public interface