From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Heilig Benedek <benecene@gmail.com>
Date: Thu, 20 Sep 2018 17:47:54 -0700
Subject: disable-redraw-lock.patch

Chromium uses a custom window titlebar implementation on Windows when DWM
is disabled (Windows 7 and earlier, non Aero theme). The native titlebar
sometimes painted over this custom titlebar, so a workaround was put in
place to lock redraws in reaction to certain events if DWM is disabled,
since the code assumes that in that case, the custom titlebar is painted.
Electron forces the use of the native titlebar, which the workaround doesn't
take into account, and still locks redraws, causing weird repainting issues
in electron (and other applications). This patch provides a way to disable
the redraw locking mechanism, which fixes these issues. The electron issue
can be found at https://github.com/electron/electron/issues/1821

diff --git a/ui/views/win/hwnd_message_handler.cc b/ui/views/win/hwnd_message_handler.cc
index ecc248f37ecaf3ced049dace1bd8e324d0937585..2377e1af24f0005703fcaee439a99d0ca9a4636b 100644
--- a/ui/views/win/hwnd_message_handler.cc
+++ b/ui/views/win/hwnd_message_handler.cc
@@ -305,6 +305,10 @@ constexpr int kSynthesizedMouseMessagesTimeDifference = 500;
 
 }  // namespace
 
+bool HWNDMessageHandlerDelegate::HasNativeFrame() const {
+  return false;
+}
+
 // A scoping class that prevents a window from being able to redraw in response
 // to invalidations that may occur within it for the lifetime of the object.
 //
@@ -356,6 +360,7 @@ class HWNDMessageHandler::ScopedRedrawLock {
         cancel_unlock_(false),
         should_lock_(owner_->IsVisible() && !owner->HasChildRenderingWindow() &&
                      ::IsWindow(hwnd_) &&
+                     !owner_->HasNativeFrame() &&
                      (!(GetWindowLong(hwnd_, GWL_STYLE) & WS_CAPTION) ||
                       !ui::win::IsAeroGlassEnabled())) {
     if (should_lock_)
@@ -969,6 +974,10 @@ HWNDMessageHandler::RegisterUnadjustedMouseEvent() {
   return scoped_enable;
 }
 
+bool HWNDMessageHandler::HasNativeFrame() {
+  return delegate_->HasNativeFrame();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // HWNDMessageHandler, gfx::WindowImpl overrides:
 
diff --git a/ui/views/win/hwnd_message_handler.h b/ui/views/win/hwnd_message_handler.h
index 4a02d86842e6c85e604d5951c6d9caf791aaf272..fa81ac2cb5714ee994caf930fc29dd755f142e8a 100644
--- a/ui/views/win/hwnd_message_handler.h
+++ b/ui/views/win/hwnd_message_handler.h
@@ -203,6 +203,8 @@ class VIEWS_EXPORT HWNDMessageHandler : public gfx::WindowImpl,
   using TouchIDs = std::set<DWORD>;
   enum class DwmFrameState { kOff, kOn };
 
+  bool HasNativeFrame();
+
   // Overridden from WindowImpl:
   HICON GetDefaultWindowIcon() const override;
   HICON GetSmallWindowIcon() const override;
diff --git a/ui/views/win/hwnd_message_handler_delegate.h b/ui/views/win/hwnd_message_handler_delegate.h
index 649163d22b7ebe5be8e2010cd30eea96587be578..d7d971937362d08f7b508244f58cc1e2d2993e9f 100644
--- a/ui/views/win/hwnd_message_handler_delegate.h
+++ b/ui/views/win/hwnd_message_handler_delegate.h
@@ -46,6 +46,8 @@ class VIEWS_EXPORT HWNDMessageHandlerDelegate {
   // True if the widget associated with this window has a non-client view.
   virtual bool HasNonClientView() const = 0;
 
+  virtual bool HasNativeFrame() const;
+
   // Returns who we want to be drawing the frame. Either the system (Windows)
   // will handle it or Chrome will custom draw it.
   virtual FrameMode GetFrameMode() const = 0;