Fix crashes in MainWidget and ApiWrap.

Telegram/SourceFiles/apiwrap.h

@@ -368,7 +368,6 @@ public:
 		not_null<PeerData*> peer,
 		const std::vector<not_null<UserData*>> &users);
 
-
 	rpl::producer<SendAction> sendActions() const {
 		return _sendActions.events();
 	}

Telegram/SourceFiles/boxes/background_preview_box.cpp

@@ -781,12 +781,12 @@ bool BackgroundPreviewBox::Start(
 		Ui::show(Box<InformBox>(tr::lng_background_bad_link(tr::now)));
 		return false;
 	}
-	controller->session().api().requestWallPaper(slug, [=](
+	controller->session().api().requestWallPaper(slug, crl::guard(controller, [=](
 			const Data::WallPaper &result) {
 		Ui::show(Box<BackgroundPreviewBox>(
 			controller,
 			result.withUrlParams(params)));
-	}, [](const RPCError &error) {
+	}), [](const RPCError &error) {
 		Ui::show(Box<InformBox>(tr::lng_background_bad_link(tr::now)));
 	});
 	return true;

Telegram/SourceFiles/core/local_url_handlers.cpp

@@ -321,12 +321,12 @@ bool ResolvePrivatePost(
 	if (!channelId || !IsServerMsgId(msgId)) {
 		return false;
 	}
-	const auto done = [=](not_null<PeerData*> peer) {
+	const auto done = crl::guard(controller, [=](not_null<PeerData*> peer) {
-		App::wnd()->sessionController()->showPeerHistory(
+		controller->showPeerHistory(
 			peer->id,
 			Window::SectionShow::Way::Forward,
 			msgId);
-	};
+	});
 	const auto fail = [=] {
 		Ui::show(Box<InformBox>(tr::lng_error_post_link_invalid(tr::now)));
 	};
@@ -388,7 +388,7 @@ bool HandleUnknown(
 		return false;
 	}
 	const auto request = match->captured(1);
-	const auto callback = [=](const MTPDhelp_deepLinkInfo &result) {
+	const auto callback = crl::guard(controller, [=](const MTPDhelp_deepLinkInfo &result) {
 		const auto text = TextWithEntities{
 			qs(result.vmessage()),
 			Api::EntitiesFromMTP(
@@ -408,7 +408,7 @@ bool HandleUnknown(
 		} else {
 			Ui::show(Box<InformBox>(text));
 		}
-	};
+	});
 	controller->session().api().requestDeepLinkInfo(request, callback);
 	return true;
 }

Telegram/SourceFiles/mainwidget.cpp

@@ -230,6 +230,7 @@ MainWidget::MainWidget(
 	not_null<Window::SessionController*> controller)
 : RpWidget(parent)
 , _controller(controller)
+, _api(&controller->session().mtp())
 , _dialogsWidth(st::columnMinimalWidthLeft)
 , _thirdColumnWidth(st::columnMinimalWidthThird)
 , _sideShadow(this)
@@ -1264,7 +1265,6 @@ void MainWidget::scheduleViewIncrement(HistoryItem *item) {
 }
 
 void MainWidget::viewsIncrement() {
-	const auto api = &session().api();
 	for (auto i = _viewsToIncrement.begin(); i != _viewsToIncrement.cend();) {
 		if (_viewsIncrementRequests.contains(i->first)) {
 			++i;
@@ -1276,7 +1276,7 @@ void MainWidget::viewsIncrement() {
 		for (const auto msgId : i->second) {
 			ids.push_back(MTP_int(msgId));
 		}
-		const auto requestId = api->request(MTPmessages_GetMessagesViews(
+		const auto requestId = _api.request(MTPmessages_GetMessagesViews(
 			i->first->input,
 			MTP_vector<MTPint>(ids),
 			MTP_bool(true)
@@ -2624,7 +2624,7 @@ void MainWidget::openPeerByName(
 			});
 		}
 	} else {
-		session().api().request(MTPcontacts_ResolveUsername(
+		_api.request(MTPcontacts_ResolveUsername(
 			MTP_string(username)
 		)).done([=](const MTPcontacts_ResolvedPeer &result) {
 			usernameResolveDone(result, msgId, startToken);

Telegram/SourceFiles/mainwidget.h

@@ -12,6 +12,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 #include "ui/rp_widget.h"
 #include "ui/effects/animations.h"
 #include "media/player/media_player_float.h"
+#include "mtproto/sender.h"
 #include "data/data_pts_waiter.h"
 
 class RPCError;
@@ -350,6 +351,7 @@ private:
 	void handleHistoryBack();
 
 	const not_null<Window::SessionController*> _controller;
+	MTP::Sender _api;
 
 	Ui::Animations::Simple _a_show;
 	bool _showBack = false;

Telegram/SourceFiles/window/window_peer_menu.cpp

@@ -1023,7 +1023,7 @@ void PeerMenuAddChannelMembers(
 		return;
 	}
 	const auto api = &channel->session().api();
-	api->requestChannelMembersForAdd(channel, [=](
+	api->requestChannelMembersForAdd(channel, crl::guard(navigation, [=](
 			const MTPchannels_ChannelParticipants &result) {
 		api->parseChannelParticipants(channel, result, [&](
 				int availableCount,
@@ -1045,7 +1045,7 @@ void PeerMenuAddChannelMembers(
 				channel,
 				{ already.begin(), already.end() });
 		});
-	});
+	}));
 }
 
 void PeerMenuAddMuteAction(

Telegram/SourceFiles/window/window_session_controller.h

@@ -116,7 +116,7 @@ struct SectionShow {
 
 class SessionController;
 
-class SessionNavigation {
+class SessionNavigation : public base::has_weak_ptr {
 public:
 	explicit SessionNavigation(not_null<Main::Session*> session);
 
@@ -156,10 +156,7 @@ private:
 
 };
 
-class SessionController
+class SessionController : public SessionNavigation, private base::Subscriber {
-	: public SessionNavigation
-	, public base::has_weak_ptr
-	, private base::Subscriber {
 public:
 	SessionController(
 		not_null<Main::Session*> session,