Add Close menu items to the context menu flyout (#9859)

Add the "Close other tabs"/"Close tabs to the right" menu items straight to the tab context menu to work around #8238.
We can't add them into a dedicated sub-menu until the upstream crash is fixed.

* [X] Closes #8238
* [X] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Documentation updated
* [ ] Schema updated.
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan.

Moved the creation of the close menu items to a single function. Once the originating crash is fixed, the sub-menu can be restored by just replacing a few lines of code.

![immagine](https://user-images.githubusercontent.com/1140981/115059601-0dbc2480-9ee7-11eb-9889-d9ef8e6e7613.png)

(cherry picked from commit 2065fa7)
(cherry picked from commit c4e02e7)

src/cascadia/TerminalApp/TabBase.cpp

@@ -45,35 +45,19 @@ namespace winrt::TerminalApp::implementation
     {
         auto weakThis{ get_weak() };
 
-        // Close
-        Controls::MenuFlyoutItem closeTabMenuItem;
-        Controls::FontIcon closeSymbol;
-        closeSymbol.FontFamily(Media::FontFamily{ L"Segoe MDL2 Assets" });
-        closeSymbol.Glyph(L"\xE711");
-
-        closeTabMenuItem.Click([weakThis](auto&&, auto&&) {
-            if (auto tab{ weakThis.get() })
-            {
-                tab->_ClosedHandlers(nullptr, nullptr);
-            }
-        });
-        closeTabMenuItem.Text(RS_(L"TabClose"));
-        closeTabMenuItem.Icon(closeSymbol);
-
         // Build the menu
         Controls::MenuFlyout newTabFlyout;
-        newTabFlyout.Items().Append(_CreateCloseSubMenu());
-        newTabFlyout.Items().Append(closeTabMenuItem);
+        _AppendCloseMenuItems(newTabFlyout);
         TabViewItem().ContextFlyout(newTabFlyout);
     }
 
     // Method Description:
-    // - Creates a sub-menu containing menu items to close multiple tabs
+    // - Append the close menu items to the context menu flyout
     // Arguments:
-    // - <none>
+    // - flyout - the menu flyout to which the close items must be appended
     // Return Value:
-    // - the created MenuFlyoutSubItem
-    Controls::MenuFlyoutSubItem TabBase::_CreateCloseSubMenu()
+    // - <none>
+    void TabBase::_AppendCloseMenuItems(winrt::Windows::UI::Xaml::Controls::MenuFlyout flyout)
     {
         auto weakThis{ get_weak() };
 
@@ -95,12 +79,30 @@ namespace winrt::TerminalApp::implementation
         });
         _closeOtherTabsMenuItem.Text(RS_(L"TabCloseOther"));
 
-        Controls::MenuFlyoutSubItem closeSubMenu;
-        closeSubMenu.Text(RS_(L"TabCloseSubMenu"));
-        closeSubMenu.Items().Append(_closeTabsAfterMenuItem);
-        closeSubMenu.Items().Append(_closeOtherTabsMenuItem);
+        // Close
+        Controls::MenuFlyoutItem closeTabMenuItem;
+        Controls::FontIcon closeSymbol;
+        closeSymbol.FontFamily(Media::FontFamily{ L"Segoe MDL2 Assets" });
+        closeSymbol.Glyph(L"\xE711");
+
+        closeTabMenuItem.Click([weakThis](auto&&, auto&&) {
+            if (auto tab{ weakThis.get() })
+            {
+                tab->_ClosedHandlers(nullptr, nullptr);
+            }
+        });
+        closeTabMenuItem.Text(RS_(L"TabClose"));
+        closeTabMenuItem.Icon(closeSymbol);
 
-        return closeSubMenu;
+        // GH#8238 append the close menu items to the flyout itself until crash in XAML is fixed
+        //Controls::MenuFlyoutSubItem closeSubMenu;
+        //closeSubMenu.Text(RS_(L"TabCloseSubMenu"));
+        //closeSubMenu.Items().Append(_closeTabsAfterMenuItem);
+        //closeSubMenu.Items().Append(_closeOtherTabsMenuItem);
+        //flyout.Items().Append(closeSubMenu);
+        flyout.Items().Append(_closeTabsAfterMenuItem);
+        flyout.Items().Append(_closeOtherTabsMenuItem);
+        flyout.Items().Append(closeTabMenuItem);
     }
 
     // Method Description:

src/cascadia/TerminalApp/TabBase.h

@@ -51,7 +51,7 @@ namespace winrt::TerminalApp::implementation
         virtual void _CreateContextMenu();
         virtual winrt::hstring _CreateToolTipTitle();
 
-        winrt::Windows::UI::Xaml::Controls::MenuFlyoutSubItem _CreateCloseSubMenu();
+        void _AppendCloseMenuItems(winrt::Windows::UI::Xaml::Controls::MenuFlyout flyout);
         void _EnableCloseMenuItems();
         void _CloseTabsAfter();
         void _CloseOtherTabs();

src/cascadia/TerminalApp/TerminalTab.cpp

@@ -784,21 +784,6 @@ namespace winrt::TerminalApp::implementation
     {
         auto weakThis{ get_weak() };
 
-        // Close
-        Controls::MenuFlyoutItem closeTabMenuItem;
-        Controls::FontIcon closeSymbol;
-        closeSymbol.FontFamily(Media::FontFamily{ L"Segoe MDL2 Assets" });
-        closeSymbol.Glyph(L"\xE711");
-
-        closeTabMenuItem.Click([weakThis](auto&&, auto&&) {
-            if (auto tab{ weakThis.get() })
-            {
-                tab->_ClosedHandlers(nullptr, nullptr);
-            }
-        });
-        closeTabMenuItem.Text(RS_(L"TabClose"));
-        closeTabMenuItem.Icon(closeSymbol);
-
         // "Color..."
         Controls::MenuFlyoutItem chooseColorMenuItem;
         Controls::FontIcon colorPickSymbol;
@@ -852,8 +837,7 @@ namespace winrt::TerminalApp::implementation
         newTabFlyout.Items().Append(chooseColorMenuItem);
         newTabFlyout.Items().Append(renameTabMenuItem);
         newTabFlyout.Items().Append(menuSeparator);
-        newTabFlyout.Items().Append(_CreateCloseSubMenu());
-        newTabFlyout.Items().Append(closeTabMenuItem);
+        _AppendCloseMenuItems(newTabFlyout);
         TabViewItem().ContextFlyout(newTabFlyout);
     }
 

src/cascadia/TerminalApp/TerminalTab.h

@@ -99,8 +99,6 @@ namespace winrt::TerminalApp::implementation
         winrt::TerminalApp::ColorPickupFlyout _tabColorPickup{};
         std::optional<winrt::Windows::UI::Color> _themeTabColor{};
         std::optional<winrt::Windows::UI::Color> _runtimeTabColor{};
-        winrt::Windows::UI::Xaml::Controls::MenuFlyoutItem _closeOtherTabsMenuItem{};
-        winrt::Windows::UI::Xaml::Controls::MenuFlyoutItem _closeTabsAfterMenuItem{};
         winrt::TerminalApp::TabHeaderControl _headerControl{};
         winrt::TerminalApp::TerminalTabStatus _tabStatus{};