Port most notebook model code over to be behind a service (#3068)

- Defines a new NotebookService in Azure Data Studio which will be used to interact with notebooks. Since notebooks can require per-file instantiation the provider is just used to create & track managers for a given URI.
- Inject this into notebook.component.ts and pass required parameters that'll be used to properly initialize a manger into the method. Actual initialization not done yet.
- Port over & recompile notebook model code
- Define most required APIs in sqlops.proposed.d.ts. In the future, these will be used by extensions to contribute their own providers.

src/sql/workbench/api/node/mainThreadNotebook.ts

@@ -0,0 +1,77 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+import * as sqlops from 'sqlops';
+import { SqlExtHostContext, SqlMainContext, ExtHostNotebookShape, MainThreadNotebookShape } from 'sql/workbench/api/node/sqlExtHost.protocol';
+import { extHostNamedCustomer } from 'vs/workbench/api/electron-browser/extHostCustomers';
+import { Disposable } from 'vs/base/common/lifecycle';
+import { IExtHostContext } from 'vs/workbench/api/node/extHost.protocol';
+import { INotebookService, INotebookProvider, INotebookManager } from 'sql/services/notebook/notebookService';
+import URI from 'vs/base/common/uri';
+
+@extHostNamedCustomer(SqlMainContext.MainThreadNotebook)
+export class MainThreadNotebook extends Disposable implements MainThreadNotebookShape {
+
+	private _proxy: ExtHostNotebookShape;
+	private _registrations: { [handle: number]: NotebookProviderWrapper } = Object.create(null);
+
+	constructor(
+		extHostContext: IExtHostContext,
+		@INotebookService private notebookService: INotebookService
+	) {
+		super();
+		if (extHostContext) {
+			this._proxy = extHostContext.getProxy(SqlExtHostContext.ExtHostNotebook);
+		}
+	}
+
+	//#region Extension host callable methods
+	public $registerNotebookProvider(providerId: string, handle: number): void {
+		let notebookProvider = new NotebookProviderWrapper(providerId, handle);
+		this._registrations[providerId] = notebookProvider;
+		this.notebookService.registerProvider(providerId, notebookProvider);
+	}
+
+	public $unregisterNotebookProvider(handle: number): void {
+		let registration = this._registrations[handle];
+		if (registration) {
+			this.notebookService.unregisterProvider(registration.providerId);
+			registration.dispose();
+			delete this._registrations[handle];
+		}
+	}
+
+	//#endregion
+
+}
+
+class NotebookProviderWrapper extends Disposable implements INotebookProvider {
+
+	constructor(public readonly providerId, public readonly handle: number) {
+		super();
+	}
+
+	getNotebookManager(notebookUri: URI): Thenable<INotebookManager> {
+		// TODO must call through to setup in the extension host
+		return Promise.resolve(new NotebookManagerWrapper(this.providerId));
+	}
+
+	handleNotebookClosed(notebookUri: URI): void {
+		// TODO implement call through to extension host
+	}
+
+
+}
+
+class NotebookManagerWrapper implements INotebookManager {
+	constructor(public readonly providerId) {
+
+	}
+	sessionManager: sqlops.nb.SessionManager;
+	contentManager: sqlops.nb.ContentManager;
+	serverManager: sqlops.nb.ServerManager;
+
+}