Derive enableDropIntoEditor from editorConfiguration.readOnly (microsoft#151777)

Fixes microsoft#151704

Author: mjbvz

src/vs/editor/browser/widget/diffEditorWidget.ts

@@ -596,7 +596,7 @@ export class DiffEditorWidget extends Disposable implements editorBrowser.IDiffE
 	}
 
 	protected _createInnerEditor(instantiationService: IInstantiationService, container: HTMLElement, options: Readonly<IEditorConstructionOptions>, editorWidgetOptions: ICodeEditorWidgetOptions): CodeEditorWidget {
-		return instantiationService.createInstance(CodeEditorWidget, container, { enableDropIntoEditor: true, ...options }, editorWidgetOptions);
+		return instantiationService.createInstance(CodeEditorWidget, container, options, editorWidgetOptions);
 	}
 
 	public override dispose(): void {
@@ -1113,6 +1113,7 @@ export class DiffEditorWidget extends Disposable implements editorBrowser.IDiffE
 			result.ariaLabel = options.originalAriaLabel;
 		}
 		result.readOnly = !this._options.originalEditable;
+		result.enableDropIntoEditor = !result.readOnly;
 		result.extraEditorClassName = 'original-in-monaco-diff-editor';
 		return {
 			...result,

src/vs/workbench/browser/parts/editor/textEditor.ts

@@ -107,6 +107,8 @@ export abstract class BaseTextEditor<T extends IEditorViewState> extends Abstrac
 		const editorConfiguration: ICodeEditorOptions = isObject(configuration.editor) ? deepClone(configuration.editor) : Object.create(null);
 		Object.assign(editorConfiguration, this.getConfigurationOverrides());
 
+		editorConfiguration.enableDropIntoEditor = !editorConfiguration.readOnly;
+
 		// ARIA label
 		editorConfiguration.ariaLabel = this.computeAriaLabel();
 
@@ -179,7 +181,7 @@ export abstract class BaseTextEditor<T extends IEditorViewState> extends Abstrac
 	protected createEditorControl(parent: HTMLElement, configuration: ICodeEditorOptions): IEditor {
 
 		// Use a getter for the instantiation service since some subclasses might use scoped instantiation services
-		return this.instantiationService.createInstance(CodeEditorWidget, parent, { enableDropIntoEditor: true, ...configuration }, {});
+		return this.instantiationService.createInstance(CodeEditorWidget, parent, configuration, {});
 	}
 
 	override async setInput(input: EditorInput, options: ITextEditorOptions | undefined, context: IEditorOpenContext, token: CancellationToken): Promise<void> {