better fix for NPE in editor.hide()

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

@@ -519,12 +519,8 @@ export class EditorGroupsControl extends Themable implements IEditorGroupsContro
 		// Clear Position
 		this.clearPosition(position);
 
-		// Take editor container offdom and hide. Check if the editor container
-		// exists in case someone manages to hide an editor before it was created
-		const editorContainer = editor.getContainer();
-		if (editorContainer) {
-			editorContainer.offDOM().hide();
-		}
+		// Take editor container offdom and hide
+		editor.getContainer().offDOM().hide();
 
 		// Adjust layout and rochade if instructed to do so
 		if (layoutAndRochade) {

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

@@ -361,7 +361,7 @@ export class EditorPart extends Part implements IEditorPart, IEditorGroupService
 
 		// Hide active one first
 		if (editorAtPosition) {
-			this.doHideEditor(position, false);
+			this.doHideEditor(editorAtPosition, position, false);
 		}
 
 		// Create Editor
@@ -592,8 +592,11 @@ export class EditorPart extends Part implements IEditorPart, IEditorGroupService
 		// Update stacks model
 		this.modifyGroups(() => this.stacks.closeGroup(group));
 
-		// Hide Editor
-		this.doHideEditor(position, true);
+		// Hide Editor if there is one
+		const editor = this.visibleEditors[position];
+		if (editor) {
+			this.doHideEditor(editor, position, true);
+		}
 
 		// Emit Change Event
 		this._onEditorsChanged.fire();
@@ -613,8 +616,7 @@ export class EditorPart extends Part implements IEditorPart, IEditorGroupService
 		}
 	}
 
-	private doHideEditor(position: Position, layoutAndRochade: boolean): void {
-		const editor = this.visibleEditors[position];
+	private doHideEditor(editor: BaseEditor, position: Position, layoutAndRochade: boolean): void {
 
 		// Hide in side by side control
 		const rochade = this.editorGroupsControl.hide(editor, position, layoutAndRochade);