Fix bugs in ShowHelp and DebugSession which broke deactivate() (#3592)

Caused by unused variables referenced only in `dispose()` methods
that were transpiled out (having been unused) and so causing
exceptions on disposal, stopping the completion of `deactivate()`.

Author: CrendKing

src/features/DebugSession.ts

@@ -25,7 +25,6 @@ export class DebugSessionFeature extends LanguageClientConsumer
     implements DebugConfigurationProvider, vscode.DebugAdapterDescriptorFactory {
 
     private sessionCount: number = 1;
-    private command: vscode.Disposable;
     private tempDebugProcess: PowerShellProcess;
     private tempSessionDetails: utils.IEditorServicesSessionDetails;
 
@@ -51,8 +50,8 @@ export class DebugSessionFeature extends LanguageClientConsumer
         return new vscode.DebugAdapterInlineImplementation(debugAdapter);
     }
 
+    // tslint:disable-next-line:no-empty
     public dispose() {
-        this.command.dispose();
     }
 
     public setLanguageClient(languageClient: LanguageClient) {

src/features/ShowHelp.ts

@@ -11,7 +11,6 @@ export const ShowHelpNotificationType =
 
 export class ShowHelpFeature extends LanguageClientConsumer {
     private command: vscode.Disposable;
-    private deprecatedCommand: vscode.Disposable;
 
     constructor(private log: Logger) {
         super();
@@ -34,7 +33,6 @@ export class ShowHelpFeature extends LanguageClientConsumer {
 
     public dispose() {
         this.command.dispose();
-        this.deprecatedCommand.dispose();
     }
 
 }