diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index e881ebc4a0e29d2d3039fede8ec4d56181a0ce74..421c7c9c87a20ee8574886411b4eab62bc4b979d 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -12,7 +12,7 @@ declare module 'vscode' {
 		export function sampleFunction(): Thenable<any>;
 	}
 
-	export namespace workspace {
+	export namespace window {
 
 		/**
 		 * Register a [TreeExplorerNodeProvider](#TreeExplorerNodeProvider).
diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index dd2939e264a3dd6bee12c5ddae64f66d1938f9e6..0a1e9bf269d0a402770355acf886e9820cf159ae 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -283,7 +283,10 @@ export function createApiFactory(initData: IInitData, threadService: IThreadServ
 			// proposed API
 			sampleFunction: proposedApiFunction(extension, () => {
 				return extHostMessageService.showMessage(Severity.Info, 'Hello Proposed Api!', []);
-			})
+			}),
+			registerTreeExplorerNodeProvider: proposedApiFunction(extension, (providerId: string, provider: vscode.TreeExplorerNodeProvider<any>) => {
+				return extHostExplorers.registerTreeExplorerNodeProvider(providerId, provider);
+			}),
 		};
 
 		// namespace: workspace
@@ -347,9 +350,6 @@ export function createApiFactory(initData: IInitData, threadService: IThreadServ
 			onWillSaveTextDocument: (listener, thisArgs?, disposables?) => {
 				return extHostDocumentSaveParticipant.onWillSaveTextDocumentEvent(listener, thisArgs, disposables);
 			},
-			registerTreeExplorerNodeProvider: proposedApiFunction(extension, (providerId: string, provider: vscode.TreeExplorerNodeProvider<any>) => {
-				return extHostExplorers.registerTreeExplorerNodeProvider(providerId, provider);
-			}),
 			onDidChangeConfiguration: (listener: () => any, thisArgs?: any, disposables?: extHostTypes.Disposable[]) => {
 				return extHostConfiguration.onDidChangeConfiguration(listener, thisArgs, disposables);
 			},