Move Tasks Panel (#5162)

* moving tasks panel

* fix css styling

* clean up code

* do a bunch of renaming

src/sql/workbench/parts/tasks/browser/tasksDataSource.ts

@@ -0,0 +1,52 @@
+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the Source EULA. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+import { ITree, IDataSource } from 'vs/base/parts/tree/browser/tree';
+import { TaskNode } from 'sql/platform/tasks/common/tasksNode';
+
+/**
+ * Implements the DataSource(that returns a parent/children of an element) for the task history
+ */
+export class TaskHistoryDataSource implements IDataSource {
+
+	/**
+	 * Returns the unique identifier of the given element.
+	 * No more than one element may use a given identifier.
+	 */
+	public getId(tree: ITree, element: any): string {
+		if (element instanceof TaskNode) {
+			return (<TaskNode>element).id;
+		} else {
+			return undefined;
+		}
+	}
+
+	/**
+	 * Returns a boolean value indicating whether the element has children.
+	 */
+	public hasChildren(tree: ITree, element: any): boolean {
+		if (element instanceof TaskNode) {
+			return (<TaskNode>element).hasChildren;
+		}
+		return false;
+	}
+
+	/**
+	 * Returns the element's children as an array in a promise.
+	 */
+	public getChildren(tree: ITree, element: any): Promise<any> {
+		if (element instanceof TaskNode) {
+			return Promise.resolve((<TaskNode>element).children);
+		}
+		return Promise.resolve(null);
+	}
+
+	/**
+	 * Returns the element's parent in a promise.
+	 */
+	public getParent(tree: ITree, element: any): Promise<any> {
+		return Promise.resolve(null);
+	}
+}