fix: touch events not recognized by WCO on windows (#35117)

patches/chromium/.patches

@@ -114,3 +114,4 @@ fix_allow_guest_webcontents_to_enter_fullscreen.patch
 disable_freezing_flags_after_init_in_node.patch
 short-circuit_permissions_checks_in_mediastreamdevicescontroller.patch
 chore_add_electron_deps_to_gitignores.patch
+chore_allow_chromium_to_handle_synthetic_mouse_events_for_touch.patch

patches/chromium/chore_allow_chromium_to_handle_synthetic_mouse_events_for_touch.patch

@@ -0,0 +1,76 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: deepak1556 <hop2deep@gmail.com>
+Date: Fri, 29 Jul 2022 00:29:35 +0900
+Subject: chore: allow chromium to handle synthetic mouse events for touch
+
+With WCO, allow chromium to handle synthetic mouse events generated for touch
+actions in the non-client caption area.
+
+diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
+index f6b37bdec2343d45447b419aeadbe2aa19493c3c..bdbf7153f27376bd68459f9cb480bff7485c9e98 100644
+--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
++++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
+@@ -1169,6 +1169,10 @@ void DesktopWindowTreeHostWin::HandleWindowScaleFactorChanged(
+   }
+ }
+ 
++bool DesktopWindowTreeHostWin::HandleMouseEventForCaption(UINT message) const {
++  return false;
++}
++
+ DesktopNativeCursorManager*
+ DesktopWindowTreeHostWin::GetSingletonDesktopNativeCursorManager() {
+   return new DesktopNativeCursorManagerWin();
+diff --git a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.h b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.h
+index 0aae49ec83b88057434af5bbfb54b10e53469918..058e5dc978e76a71fa02dc9e275592f3c39befea 100644
+--- a/ui/views/widget/desktop_aura/desktop_window_tree_host_win.h
++++ b/ui/views/widget/desktop_aura/desktop_window_tree_host_win.h
+@@ -263,6 +263,7 @@ class VIEWS_EXPORT DesktopWindowTreeHostWin
+   void HandleWindowSizeChanging() override;
+   void HandleWindowSizeUnchanged() override;
+   void HandleWindowScaleFactorChanged(float window_scale_factor) override;
++  bool HandleMouseEventForCaption(UINT message) const override;
+ 
+   Widget* GetWidget();
+   const Widget* GetWidget() const;
+diff --git a/ui/views/win/hwnd_message_handler.cc b/ui/views/win/hwnd_message_handler.cc
+index 3b546cf67089e6677fc668b4d1d6c0863282dff5..c6810f162806b36494885b2f63982a756d4dcd38 100644
+--- a/ui/views/win/hwnd_message_handler.cc
++++ b/ui/views/win/hwnd_message_handler.cc
+@@ -3129,15 +3129,19 @@ LRESULT HWNDMessageHandler::HandleMouseEventInternal(UINT message,
+       SetMsgHandled(FALSE);
+     // We must let Windows handle the caption buttons if it's drawing them, or
+     // they won't work.
++    bool simulate_mouse_event_for_caption = false;
+     if (delegate_->GetFrameMode() == FrameMode::SYSTEM_DRAWN &&
+         (hittest == HTCLOSE || hittest == HTMINBUTTON ||
+          hittest == HTMAXBUTTON)) {
+-      SetMsgHandled(FALSE);
++      simulate_mouse_event_for_caption =
++          delegate_->HandleMouseEventForCaption(message);
++      if (!simulate_mouse_event_for_caption)
++        SetMsgHandled(FALSE);
+     }
+     // Let resize events fall through. Ignore everything else, as we're either
+     // letting Windows handle it above or we've already handled the equivalent
+     // touch message.
+-    if (!IsHitTestOnResizeHandle(hittest))
++    if (!IsHitTestOnResizeHandle(hittest) && !simulate_mouse_event_for_caption)
+       return 0;
+   }
+ 
+diff --git a/ui/views/win/hwnd_message_handler_delegate.h b/ui/views/win/hwnd_message_handler_delegate.h
+index 5dbb192d0840ca0ded61397c399b774a8cb05cce..098a9c3140e9e140fdc8f0dc9cf4e8ec84451221 100644
+--- a/ui/views/win/hwnd_message_handler_delegate.h
++++ b/ui/views/win/hwnd_message_handler_delegate.h
+@@ -258,6 +258,10 @@ class VIEWS_EXPORT HWNDMessageHandlerDelegate {
+   // Called when the window scale factor has changed.
+   virtual void HandleWindowScaleFactorChanged(float window_scale_factor) = 0;
+ 
++  // Called when synthetic mouse event is generated for touch event on
++  // caption buttons.
++  virtual bool HandleMouseEventForCaption(UINT message) const = 0;
++
+  protected:
+   virtual ~HWNDMessageHandlerDelegate() = default;
+ };

shell/browser/ui/win/electron_desktop_window_tree_host_win.cc

@@ -95,6 +95,27 @@ bool ElectronDesktopWindowTreeHostWin::GetClientAreaInsets(
   return false;
 }
 
+bool ElectronDesktopWindowTreeHostWin::HandleMouseEventForCaption(
+    UINT message) const {
+  // Windows does not seem to generate WM_NCPOINTERDOWN/UP touch events for
+  // caption buttons with WCO. This results in a no-op for
+  // HWNDMessageHandler::HandlePointerEventTypeTouchOrNonClient and
+  // WM_SYSCOMMAND is not generated for the touch action. However, Windows will
+  // also generate a mouse event for every touch action and this gets handled in
+  // HWNDMessageHandler::HandleMouseEventInternal.
+  // With https://chromium-review.googlesource.com/c/chromium/src/+/1048877/
+  // Chromium lets the OS handle caption buttons for FrameMode::SYSTEM_DRAWN but
+  // again this does not generate the SC_MINIMIZE, SC_MAXIMIZE, SC_RESTORE
+  // commands when Non-client mouse events are generated for HTCLOSE,
+  // HTMINBUTTON, HTMAXBUTTON. To workaround this issue, wit this delegate we
+  // let chromium handle the mouse events via
+  // HWNDMessageHandler::HandleMouseInputForCaption instead of the OS and this
+  // will generate the necessary system commands to perform caption button
+  // actions due to the DefWindowProc call.
+  // https://source.chromium.org/chromium/chromium/src/+/main:ui/views/win/hwnd_message_handler.cc;l=3611
+  return native_window_view_->IsWindowControlsOverlayEnabled();
+}
+
 void ElectronDesktopWindowTreeHostWin::OnNativeThemeUpdated(
     ui::NativeTheme* observed_theme) {
   win::SetDarkModeForWindow(GetAcceleratedWidget());

shell/browser/ui/win/electron_desktop_window_tree_host_win.h

@@ -36,6 +36,7 @@ class ElectronDesktopWindowTreeHostWin : public views::DesktopWindowTreeHostWin,
   bool GetDwmFrameInsetsInPixels(gfx::Insets* insets) const override;
   bool GetClientAreaInsets(gfx::Insets* insets,
                            HMONITOR monitor) const override;
+  bool HandleMouseEventForCaption(UINT message) const override;
 
   // ui::NativeThemeObserver:
   void OnNativeThemeUpdated(ui::NativeTheme* observed_theme) override;