fix: Avoid crashing in NativeViewHost::SetParentAccessible on Windows (…

…#26952)

This fixes #26905. The patch was obtained from @deepak1556, who in turn
got it from the Microsoft Teams folks.

I believe the crash started happening due to the changes in
https://chromium.googlesource.com/chromium/src.git/+/5c6c8e994bce2bfb867279ae5068e9f9134e70c3%5E!/#F15

This affects Electron 9 and later.

Notes: Fix occasional crash on Windows

Co-authored-by: Biru Mohanathas <birunthan@mohanathas.com>

patches/chromium/.patches

@@ -104,3 +104,4 @@ chore_expose_v8_initialization_isolate_callbacks.patch
 export_gin_v8platform_pageallocator_for_usage_outside_of_the_gin.patch
 use_public_apis_to_determine_if_a_font_is_a_system_font_in_mas_build.patch
 cherry-pick-47e21abe349a.patch
+fix_setparentacessibile_crash_win.patch

patches/chromium/fix_setparentacessibile_crash_win.patch

@@ -0,0 +1,28 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Biru Mohanathas <birunthan@mohanathas.com>
+Date: Thu, 10 Dec 2020 19:02:37 +0200
+Subject: fix crash in NativeViewHost::SetParentAccessible
+
+This fixes random crashes on Windows 10. It presumably started happening
+after the changes in
+https://chromium.googlesource.com/chromium/src.git/+/5c6c8e994bce2bfb867279ae5068e9f9134e70c3%5E!/#F15
+
+For context, see: https://github.com/electron/electron/issues/26905
+
+This patch can likely be upstreamed. The crash cannot be fixed without
+patching something in Chromium - this is the least invasive change.
+
+diff --git a/ui/views/controls/native/native_view_host.cc b/ui/views/controls/native/native_view_host.cc
+index f9e1aa1b455ae49b59d53a75ae0634d0c092a130..4785f0c0368e0ab22db0cc968ad85d23a9b26240 100644
+--- a/ui/views/controls/native/native_view_host.cc
++++ b/ui/views/controls/native/native_view_host.cc
+@@ -55,6 +55,9 @@ void NativeViewHost::Detach() {
+ }
+
+ void NativeViewHost::SetParentAccessible(gfx::NativeViewAccessible accessible) {
++  if (!native_wrapper_.get())
++    return;
++
+   native_wrapper_->SetParentAccessible(accessible);
+ }
+