Avoid dangling company purchase timeout when no clients connected to company

src/company_cmd.cpp

@@ -684,6 +684,16 @@ static void HandleBankruptcyTakeover(Company *c)
 
 	/* We're currently asking some company to buy 'us' */
 	if (c->bankrupt_timeout != 0) {
+		if (!Company::IsValidID(c->bankrupt_last_asked)) {
+			c->bankrupt_timeout = 0;
+			return;
+		}
+		if (_network_server && Company::IsValidHumanID(c->bankrupt_last_asked) && !NetworkCompanyHasClients(c->bankrupt_last_asked)) {
+			/* This company can no longer accept the offer as there are no clients connected, decline the offer on the company's behalf */
+			Backup<CompanyID> cur_company(_current_company, c->bankrupt_last_asked, FILE_LINE);
+			DoCommandP(0, c->index, 0, CMD_DECLINE_BUY_COMPANY | CMD_NO_SHIFT_ESTIMATE);
+			cur_company.Restore();
+		}
 		c->bankrupt_timeout -= MAX_COMPANIES;
 		if (c->bankrupt_timeout > 0) return;
 		c->bankrupt_timeout = 0;
@@ -731,7 +741,7 @@ static void HandleBankruptcyTakeover(Company *c)
 	} else if (!_networking || (_network_server && !NetworkCompanyHasClients(best->index))) {
 		/* This company can never accept the offer as there are no clients connected, decline the offer on the company's behalf */
 		Backup<CompanyID> cur_company(_current_company, best->index, FILE_LINE);
-		DoCommandP(0, c->index, 0, CMD_DECLINE_BUY_COMPANY);
+		DoCommandP(0, c->index, 0, CMD_DECLINE_BUY_COMPANY | CMD_NO_SHIFT_ESTIMATE);
 		cur_company.Restore();
 	}
 }

src/company_gui.cpp

@@ -2891,7 +2891,7 @@ struct BuyCompanyWindow : Window {
 	~BuyCompanyWindow()
 	{
 		const Company *c = Company::GetIfValid((CompanyID)this->window_number);
-		if (c != nullptr && HasBit(c->bankrupt_asked, this->owner)) {
+		if (c != nullptr && HasBit(c->bankrupt_asked, this->owner) && _current_company == this->owner) {
 			EnqueueDoCommandP(NewCommandContainerBasic(0, this->window_number, 0, CMD_DECLINE_BUY_COMPANY | CMD_NO_SHIFT_ESTIMATE));
 		}
 	}