Everywhere: Rename ASSERT => VERIFY

(...and ASSERT_NOT_REACHED => VERIFY_NOT_REACHED)

Since all of these checks are done in release builds as well,
let's rename them to VERIFY to prevent confusion, as everyone is
used to assertions being compiled out in release.

We can introduce a new ASSERT macro that is specifically for debug
checks, but I'm doing this wholesale conversion first since we've
accumulated thousands of these already, and it's not immediately
obvious which ones are suitable for ASSERT.

Userland/Libraries/LibGUI/Window.cpp

@@ -228,7 +228,7 @@ String Window::title() const
 
 Gfx::IntRect Window::rect_in_menubar() const
 {
-    ASSERT(m_window_type == WindowType::MenuApplet);
+    VERIFY(m_window_type == WindowType::MenuApplet);
     return WindowServerConnection::the().send_sync<Messages::WindowServer::GetWindowRectInMenubar>(m_window_id)->rect();
 }
 
@@ -330,7 +330,7 @@ void Window::handle_drop_event(DropEvent& event)
         return;
     auto result = m_main_widget->hit_test(event.position());
     auto local_event = make<DropEvent>(result.local_position, event.text(), event.mime_data());
-    ASSERT(result.widget);
+    VERIFY(result.widget);
     result.widget->dispatch_event(*local_event, this);
 
     Application::the()->set_drag_hovered_widget({}, nullptr);
@@ -358,7 +358,7 @@ void Window::handle_mouse_event(MouseEvent& event)
         return;
     auto result = m_main_widget->hit_test(event.position());
     auto local_event = make<MouseEvent>((Event::Type)event.type(), result.local_position, event.buttons(), event.button(), event.modifiers(), event.wheel_delta());
-    ASSERT(result.widget);
+    VERIFY(result.widget);
     set_hovered_widget(result.widget);
     if (event.buttons() != 0 && !m_automatic_cursor_tracking_widget)
         m_automatic_cursor_tracking_widget = *result.widget;
@@ -374,7 +374,7 @@ void Window::handle_multi_paint_event(MultiPaintEvent& event)
     if (!m_main_widget)
         return;
     auto rects = event.rects();
-    ASSERT(!rects.is_empty());
+    VERIFY(!rects.is_empty());
     if (m_back_store && m_back_store->size() != event.window_size()) {
         // Eagerly discard the backing store if we learn from this paint event that it needs to be bigger.
         // Otherwise we would have to wait for a resize event to tell us. This way we don't waste the
@@ -384,12 +384,12 @@ void Window::handle_multi_paint_event(MultiPaintEvent& event)
     bool created_new_backing_store = !m_back_store;
     if (!m_back_store) {
         m_back_store = create_backing_store(event.window_size());
-        ASSERT(m_back_store);
+        VERIFY(m_back_store);
     } else if (m_double_buffering_enabled) {
         bool still_has_pixels = m_back_store->bitmap().set_nonvolatile();
         if (!still_has_pixels) {
             m_back_store = create_backing_store(event.window_size());
-            ASSERT(m_back_store);
+            VERIFY(m_back_store);
             created_new_backing_store = true;
         }
     }
@@ -497,7 +497,7 @@ void Window::handle_drag_move_event(DragEvent& event)
     if (!m_main_widget)
         return;
     auto result = m_main_widget->hit_test(event.position());
-    ASSERT(result.widget);
+    VERIFY(result.widget);
 
     Application::the()->set_drag_hovered_widget({}, result.widget, result.local_position, event.mime_types());
 
@@ -688,7 +688,7 @@ void Window::set_has_alpha_channel(bool value)
 
 void Window::set_double_buffering_enabled(bool value)
 {
-    ASSERT(!is_visible());
+    VERIFY(!is_visible());
     m_double_buffering_enabled = value;
 }
 
@@ -742,7 +742,7 @@ void Window::flip(const Vector<Gfx::IntRect, 32>& dirty_rects)
 
     if (!m_back_store || m_back_store->size() != m_front_store->size()) {
         m_back_store = create_backing_store(m_front_store->size());
-        ASSERT(m_back_store);
+        VERIFY(m_back_store);
         memcpy(m_back_store->bitmap().scanline(0), m_front_store->bitmap().scanline(0), m_front_store->bitmap().size_in_bytes());
         m_back_store->bitmap().set_volatile();
         return;
@@ -760,7 +760,7 @@ OwnPtr<WindowBackingStore> Window::create_backing_store(const Gfx::IntSize& size
 {
     auto format = m_has_alpha_channel ? Gfx::BitmapFormat::RGBA32 : Gfx::BitmapFormat::RGB32;
 
-    ASSERT(!size.is_empty());
+    VERIFY(!size.is_empty());
     size_t pitch = Gfx::Bitmap::minimum_pitch(size.width(), format);
     size_t size_in_bytes = size.height() * pitch;
 
@@ -779,7 +779,7 @@ OwnPtr<WindowBackingStore> Window::create_backing_store(const Gfx::IntSize& size
 
 void Window::set_modal(bool modal)
 {
-    ASSERT(!is_visible());
+    VERIFY(!is_visible());
     m_modal = modal;
 }
 
@@ -795,7 +795,7 @@ void Window::set_icon(const Gfx::Bitmap* icon)
     Gfx::IntSize icon_size = icon ? icon->size() : Gfx::IntSize(16, 16);
 
     m_icon = Gfx::Bitmap::create(Gfx::BitmapFormat::RGBA32, icon_size);
-    ASSERT(m_icon);
+    VERIFY(m_icon);
     if (icon) {
         Painter painter(*m_icon);
         painter.blit({ 0, 0 }, *icon, icon->rect());
@@ -910,7 +910,7 @@ void Window::refresh_system_theme()
 void Window::for_each_window(Badge<WindowServerConnection>, Function<void(Window&)> callback)
 {
     for (auto& e : *reified_windows) {
-        ASSERT(e.value);
+        VERIFY(e.value);
         callback(*e.value);
     }
 }
@@ -1003,7 +1003,7 @@ void Window::did_remove_widget(Badge<Widget>, Widget& widget)
 
 void Window::set_progress(int progress)
 {
-    ASSERT(m_window_id);
+    VERIFY(m_window_id);
     WindowServerConnection::the().post_message(Messages::WindowServer::SetWindowProgress(m_window_id, progress));
 }
 
@@ -1040,7 +1040,7 @@ void Window::did_disable_focused_widget(Badge<Widget>)
 
 bool Window::is_active() const
 {
-    ASSERT(Application::the());
+    VERIFY(Application::the());
     return this == Application::the()->active_window();
 }