From 4b3d0b27ad902fca01c62a26534c3893619ecb8d Mon Sep 17 00:00:00 2001
From: Shelley Vohr <shelley.vohr@gmail.com>
Date: Thu, 2 Apr 2020 18:00:56 -0700
Subject: [PATCH 1/3] fix: nullptr check when closing windows

---
 shell/browser/window_list.cc | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/shell/browser/window_list.cc b/shell/browser/window_list.cc
index 494114edd9e03..688f2577a65d8 100644
--- a/shell/browser/window_list.cc
+++ b/shell/browser/window_list.cc
@@ -84,16 +84,19 @@ void WindowList::CloseAllWindows() {
 #if defined(OS_MACOSX)
   std::reverse(windows.begin(), windows.end());
 #endif
-  for (auto* const& window : windows)
-    if (!window->IsClosed())
+  for (auto* const& window : windows) {
+    if (window && !window->IsClosed())
       window->Close();
+  }
 }
 
 // static
 void WindowList::DestroyAllWindows() {
   WindowVector windows = GetInstance()->windows_;
-  for (auto* const& window : windows)
-    window->CloseImmediately();  // e.g. Destroy()
+  for (auto* const& window : windows) {
+    if (window)
+      window->CloseImmediately();
+  }
 }
 
 WindowList::WindowList() {}

From 9817444d5faee0f64c04ecc5d3286e3e329eb232 Mon Sep 17 00:00:00 2001
From: Shelley Vohr <shelley.vohr@gmail.com>
Date: Tue, 7 Apr 2020 07:20:43 -0700
Subject: [PATCH 2/3] Address feedback from @zcbenz

---
 shell/browser/window_list.cc | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/shell/browser/window_list.cc b/shell/browser/window_list.cc
index 688f2577a65d8..9a68673597b2b 100644
--- a/shell/browser/window_list.cc
+++ b/shell/browser/window_list.cc
@@ -10,6 +10,18 @@
 #include "shell/browser/native_window.h"
 #include "shell/browser/window_list_observer.h"
 
+namespace {
+template <typename T>
+std::vector<base::WeakPtr<T>> ConvertToWeakPtrVector(std::vector<T*> raw_ptrs) {
+  std::vector<base::WeakPtr<T>> converted_to_weak;
+  for (auto* raw_ptr : raw_ptrs) {
+    base::WeakPtr<T> weak = raw_ptr->GetWeakPtr();
+    converted_to_weak.push_back(weak);
+  }
+  return converted_to_weak;
+}
+}  // namespace
+
 namespace electron {
 
 // static
@@ -93,7 +105,10 @@ void WindowList::CloseAllWindows() {
 // static
 void WindowList::DestroyAllWindows() {
   WindowVector windows = GetInstance()->windows_;
-  for (auto* const& window : windows) {
+  std::vector<base::WeakPtr<NativeWindow>> weak_windows =
+      ConvertToWeakPtrVector(windows);
+
+  for (const auto& window : weak_windows) {
     if (window)
       window->CloseImmediately();
   }

From 1809661f723b93ca1f463be06abebbad4c022234 Mon Sep 17 00:00:00 2001
From: Shelley Vohr <shelley.vohr@gmail.com>
Date: Tue, 7 Apr 2020 13:31:54 -0700
Subject: [PATCH 3/3] use weakptr vector in CloseAllWindows

---
 shell/browser/window_list.cc | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/shell/browser/window_list.cc b/shell/browser/window_list.cc
index 9a68673597b2b..8dd4bf37745ee 100644
--- a/shell/browser/window_list.cc
+++ b/shell/browser/window_list.cc
@@ -14,9 +14,9 @@ namespace {
 template <typename T>
 std::vector<base::WeakPtr<T>> ConvertToWeakPtrVector(std::vector<T*> raw_ptrs) {
   std::vector<base::WeakPtr<T>> converted_to_weak;
+  converted_to_weak.reserve(raw_ptrs.size());
   for (auto* raw_ptr : raw_ptrs) {
-    base::WeakPtr<T> weak = raw_ptr->GetWeakPtr();
-    converted_to_weak.push_back(weak);
+    converted_to_weak.push_back(raw_ptr->GetWeakPtr());
   }
   return converted_to_weak;
 }
@@ -92,11 +92,12 @@ void WindowList::RemoveObserver(WindowListObserver* observer) {
 
 // static
 void WindowList::CloseAllWindows() {
-  WindowVector windows = GetInstance()->windows_;
+  std::vector<base::WeakPtr<NativeWindow>> weak_windows =
+      ConvertToWeakPtrVector(GetInstance()->windows_);
 #if defined(OS_MACOSX)
-  std::reverse(windows.begin(), windows.end());
+  std::reverse(weak_windows.begin(), weak_windows.end());
 #endif
-  for (auto* const& window : windows) {
+  for (const auto& window : weak_windows) {
     if (window && !window->IsClosed())
       window->Close();
   }
@@ -104,9 +105,8 @@ void WindowList::CloseAllWindows() {
 
 // static
 void WindowList::DestroyAllWindows() {
-  WindowVector windows = GetInstance()->windows_;
   std::vector<base::WeakPtr<NativeWindow>> weak_windows =
-      ConvertToWeakPtrVector(windows);
+      ConvertToWeakPtrVector(GetInstance()->windows_);
 
   for (const auto& window : weak_windows) {
     if (window)