Merge pull request #1484 from MicrosoftEdge/api-browser-task-manager-draft

Create BrowserTaskManager.md

Author: schuylergleaves

specs/BrowserTaskManager.md

@@ -0,0 +1,81 @@
+# Background
+The WebView2 team has been asked to provide an API to expose the Browser Task
+Manager. The Browser Task Manager is a window helpful for debugging that 
+displays the different processes associated with the current browser process and 
+what they're used for. For instance, it could denote that a particular process 
+is a renderer process and would show the different web pages rendered by that 
+process. In a chromium browser it can be opened by the end user by pressing 
+`Shift+Esc` or from the DevTools window's title bar's context menu entry 
+`Browser task manager`. For WebView2 applications, we block the 
+`Shift+Esc` shortcut, but the task manager can still be opened via the 
+`Browser task manager` entry.
+
+At the current time, it is expected that the user will close the Task 
+Manager manually, so we do not need to provide an API to close it.
+
+In this document we describe the updated API. We'd appreciate your feedback.
+
+# Description
+We propose extending `CoreWebView2` to provide an `OpenTaskManagerWindow` 
+method. This method will open a new window containing the task manager. 
+If the task manager is already opened, this method will do nothing.
+
+# Examples
+## C++: Open Task Manager
+
+``` cpp
+wil::com_ptr<ICoreWebView2_5> m_webview;
+
+// This method could be called from a menu bar item, such as 
+// [Script -> Open Task Manager Window]. 
+void ScriptComponent::OpenTaskManagerWindow()
+{
+    CHECK_FAILURE(m_webview->OpenTaskManagerWindow());
+}
+```
+
+## C#: Open Task Manager
+```c#
+private WebView2 m_webview;
+
+// This method could be called from a menu bar item, such as 
+// [Script -> Open Task Manager Window]. 
+void OpenTaskManagerWindow()
+{
+    m_webview.CoreWebView2.OpenTaskManagerWindow();
+}
+```
+
+# API Details
+## C++
+```
+/// This is a continuation of the `ICoreWebView2_4` interface
+[uuid(20d02d59-6df2-42dc-bd06-f98a694b1302), object, pointer_default(unique)]
+interface ICoreWebView2_5 : ICoreWebView2_4 {
+    /// Opens the Browser Task Manager view as a new window. Does nothing
+    /// if run when the Browser Task Manager is already open.
+    /// WebView2 currently blocks the `Shift+Esc` shortcut for opening the
+    /// task manager. An end user can open the browser task manager manually
+    /// via the `Browser task manager` entry of the DevTools window's title 
+    /// bar's context menu.
+    HRESULT OpenTaskManagerWindow();
+}
+```
+
+## C#
+```c#
+namespace Microsoft.Web.WebView2.Core
+{
+    runtimeclass CoreWebView2
+    {
+        // There are many methods and properties of ICoreWebView2_* which I am
+        // not including here for simplicity. 
+
+        [interface_name("Microsoft.Web.WebView2.Core.ICoreWebView2_5")]
+        {
+            // ICoreWebView2_5 members
+            void OpenTaskManagerWindow();
+        }
+    }
+}
+```