make it possible to change a SCMResourceGroup's label

src/vs/vscode.d.ts

@@ -4735,7 +4735,7 @@ declare module 'vscode' {
 		/**
 		 * The label of this source control resource group.
 		 */
-		readonly label: string;
+		label: string;
 
 		/**
 		 * Whether this source control resource group is hidden when it contains

src/vs/workbench/api/node/extHost.protocol.ts

@@ -295,6 +295,7 @@ export abstract class MainThreadSCMShape {
 
 	$registerGroup(sourceControlHandle: number, handle: number, id: string, label: string): void { throw ni(); }
 	$updateGroup(sourceControlHandle: number, handle: number, features: SCMGroupFeatures): void { throw ni(); }
+	$updateGroupLabel(sourceControlHandle: number, handle: number, label: string): void { throw ni(); }
 	$updateGroupResourceStates(sourceControlHandle: number, groupHandle: number, resources: SCMRawResource[]): void { throw ni(); }
 	$unregisterGroup(sourceControlHandle: number, handle: number): void { throw ni(); }
 

src/vs/workbench/api/node/extHostSCM.ts

@@ -81,6 +81,11 @@ class ExtHostSourceControlResourceGroup implements vscode.SourceControlResourceG
 		return this._label;
 	}
 
+	set label(label: string) {
+		this._label = label;
+		this._proxy.$updateGroupLabel(this._sourceControlHandle, this._handle, label);
+	}
+
 	private _hideWhenEmpty: boolean | undefined = undefined;
 
 	get hideWhenEmpty(): boolean | undefined {

src/vs/workbench/api/node/mainThreadSCM.ts

@@ -137,6 +137,17 @@ class MainThreadSCMProvider implements ISCMProvider {
 		this._onDidChange.fire();
 	}
 
+	$updateGroupLabel(handle: number, label: string): void {
+		const group = this._groupsByHandle[handle];
+
+		if (!group) {
+			return;
+		}
+
+		group.label = label;
+		this._onDidChange.fire();
+	}
+
 	$updateGroupResourceStates(groupHandle: number, resources: SCMRawResource[]): void {
 		const group = this._groupsByHandle[groupHandle];
 
@@ -263,6 +274,16 @@ export class MainThreadSCM extends MainThreadSCMShape {
 		provider.$updateGroup(groupHandle, features);
 	}
 
+	$updateGroupLabel(sourceControlHandle: number, groupHandle: number, label: string): void {
+		const provider = this._sourceControls[sourceControlHandle];
+
+		if (!provider) {
+			return;
+		}
+
+		provider.$updateGroupLabel(groupHandle, label);
+	}
+
 	$updateGroupResourceStates(sourceControlHandle: number, groupHandle: number, resources: SCMRawResource[]): void {
 		const provider = this._sourceControls[sourceControlHandle];