clean up (microsoft#165990)

Author: sandy081

src/vs/platform/extensionManagement/node/extensionManagementService.ts

@@ -751,9 +751,6 @@ export class InstallGalleryExtensionTask extends InstallExtensionTask {
 			this.wasVerified = !!verified;
 			this.validateManifest(location.fsPath);
 			const local = await this.installExtension({ zipPath: location.fsPath, key: ExtensionKey.create(this.gallery), metadata }, token);
-			if (existingExtension && !this.options.profileLocation && (existingExtension.targetPlatform !== local.targetPlatform || semver.neq(existingExtension.manifest.version, local.manifest.version))) {
-				await this.extensionsScanner.setUninstalled(existingExtension);
-			}
 			return { local, metadata };
 		} catch (error) {
 			try {