Minor clean up

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

@@ -119,7 +119,6 @@ export abstract class MainThreadEditorsShape {
 
 export abstract class MainThreadTreeExplorersShape {
 	$registerTreeExplorerNodeProvider(providerId: string): void { throw ni(); }
-	$unregisterTreeExplorerNodeProvider(providerId: string): void { throw ni(); }
 }
 
 export abstract class MainThreadErrorsShape {

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

@@ -36,9 +36,7 @@ export class ExtHostTreeExplorers extends ExtHostTreeExplorersShape {
 		this._treeExplorerNodeProviders[providerId] = provider;
 
 		return new Disposable(() => {
-			if (delete this._treeExplorerNodeProviders[providerId]) {
-				this._proxy.$unregisterTreeExplorerNodeProvider(providerId);
-			}
+			delete this._treeExplorerNodeProviders[providerId];
 		});
 	}
 

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

@@ -35,8 +35,4 @@ export class MainThreadTreeExplorers extends MainThreadTreeExplorersShape {
 			}
 		});
 	}
-
-	$unregisterTreeExplorerNodeProvider(providerId: string): void {
-
-	}
 }