Show "Translate" in three-dot if bar was hidden.

Telegram/SourceFiles/history/view/history_view_translate_bar.cpp

@@ -83,20 +83,30 @@ void TranslateBar::setup(not_null<History*> history) {
 	_wrap.geometryValue(
 	) | rpl::start_with_next([=](QRect rect) {
 		updateShadowGeometry(rect);
-	updateControlsGeometry(rect);
+		updateControlsGeometry(rect);
 	}, _wrap.lifetime());
 
 	const auto button = static_cast<Ui::FlatButton*>(_wrap.entity());
-	button->setClickedCallback([=] {
-		const auto to = history->translatedTo()
-			? LanguageId()
-			: Core::App().settings().translateTo();
-		history->translateTo(to);
+	const auto translateTo = [=](LanguageId id) {
+		history->translateTo(id);
 		if (const auto migrated = history->migrateFrom()) {
-			migrated->translateTo(to);
+			migrated->translateTo(id);
 		}
+	};
+	button->setClickedCallback([=] {
+		translateTo(history->translatedTo()
+			? LanguageId()
+			: Core::App().settings().translateTo());
 	});
 
+	Core::App().settings().translateToValue(
+	) | rpl::filter([=](LanguageId should) {
+		const auto now = history->translatedTo();
+		return now && (now != should);
+	}) | rpl::start_with_next([=](LanguageId should) {
+		translateTo(should);
+	}, _wrap.lifetime());
+
 	const auto label = Ui::CreateChild<Ui::FlatLabel>(
 		button,
 		st::historyTranslateLabel);

Telegram/SourceFiles/window/window_peer_menu.cpp

@@ -270,6 +270,7 @@ private:
 	void addViewDiscussion();
 	void addToggleTopicClosed();
 	void addExportChat();
+	void addTranslate();
 	void addReport();
 	void addNewContact();
 	void addShareContact();
@@ -776,6 +777,23 @@ void Filler::addExportChat() {
 		&st::menuIconExport);
 }
 
+void Filler::addTranslate() {
+	if (_peer->translationFlag() != PeerData::TranslationFlag::Disabled
+		|| !_peer->session().premium()
+		|| !Core::App().settings().translateChatEnabled()) {
+		return;
+	}
+	const auto history = _peer->owner().historyLoaded(_peer);
+	if (!history
+		|| !history->translateOfferedFrom()
+		|| history->translatedTo()) {
+		return;
+	}
+	_addAction(tr::lng_context_translate(tr::now), [=] {
+		history->peer->saveTranslationDisabled(false);
+	}, &st::menuIconTranslate);
+}
+
 void Filler::addReport() {
 	const auto chat = _peer->asChat();
 	const auto channel = _peer->asChannel();
@@ -1174,6 +1192,7 @@ void Filler::fillHistoryActions() {
 	addThemeEdit();
 	addViewDiscussion();
 	addExportChat();
+	addTranslate();
 	addReport();
 	addClearHistory();
 	addDeleteChat();