make embedded preview editor use shadows and let it use editor contribs (microsoft#185245)

microsoft/vscode-copilot#350

Author: jrieken

src/vs/workbench/contrib/inlineChat/browser/inlineChatLivePreviewWidget.ts

@@ -370,13 +370,18 @@ export class InlineChatFileCreatePreviewWidget extends ZoneWidget {
 		super.create();
 
 		this._title = instaService.createInstance(ResourceLabel, this._elements.title, { supportIcons: true });
+
+		const contributions = EditorExtensionsRegistry
+			.getEditorContributions()
+			.filter(c => c.id !== INLINE_CHAT_ID);
+
 		this._previewEditor = instaService.createInstance(EmbeddedCodeEditorWidget, this._elements.editor, {
 			scrollBeyondLastLine: false,
 			stickyScroll: { enabled: false },
 			readOnly: true,
 			minimap: { enabled: false },
-			scrollbar: { alwaysConsumeMouseWheel: false },
-		}, { isSimpleWidget: true, contributions: [] }, parentEditor);
+			scrollbar: { alwaysConsumeMouseWheel: false, useShadows: true },
+		}, { isSimpleWidget: true, contributions }, parentEditor);
 
 		const doStyle = () => {
 			const theme = themeService.getColorTheme();