Fixed context menu showing when deselecting unit with right click (fixes #1908)

Do note the mouse_handler::unselected_reach_ flag is only used for this one bugfix, and I haven't
tested whether it needs to be set any time game_display::unhighlight_reach is called.

src/game_display.cpp

@@ -576,14 +576,17 @@ void game_display::highlight_another_reach(const pathfind::paths &paths_list)
 	reach_map_changed_ = true;
 }
 
-void game_display::unhighlight_reach()
+bool game_display::unhighlight_reach()
 {
-	reach_map_ = reach_map();
-	reach_map_changed_ = true;
+	reach_map_changed_ = !reach_map_.empty();
+
+	if(reach_map_changed_) {
+		reach_map_.clear();
+	}
+
+	return reach_map_changed_;
 }
 
-
-
 void game_display::invalidate_route()
 {
 	for(std::vector<map_location>::const_iterator i = route_.steps.begin();

src/game_display.hpp

@@ -105,7 +105,7 @@ public:
 	void highlight_another_reach(const pathfind::paths &paths_list);
 
 	/** Reset highlighting of paths. */
-	void unhighlight_reach();
+	bool unhighlight_reach();
 
 	/**
 	 * Sets the route along which footsteps are drawn to show movement of a

src/mouse_events.cpp

@@ -485,7 +485,12 @@ void mouse_handler::mouse_press(const SDL_MouseButtonEvent& event, const bool br
 
 bool mouse_handler::right_click_show_menu(int x, int y, const bool /*browse*/)
 {
-	return (selected_hex_.valid() ? false : sdl::point_in_rect(x, y, gui().map_area()));
+	if(selected_hex_.valid() || unselected_reach_) {
+		unselected_reach_ = false;
+		return false;
+	}
+
+	return sdl::point_in_rect(x, y, gui().map_area());
 }
 
 void mouse_handler::select_or_action(bool browse)
@@ -784,7 +789,7 @@ void mouse_handler::select_hex(const map_location& hex, const bool browse, const
 		gui_->highlight_another_reach(reaching_unit_locations);
 	} else {
 		if(!pc_.gamestate().board_.units_.find(last_hex_)) {
-			gui_->unhighlight_reach();
+			unselected_reach_ = gui_->unhighlight_reach();
 		}
 
 		current_paths_ = pathfind::paths();

src/mouse_events.hpp

@@ -137,6 +137,7 @@ private:
 	pathfind::marked_route current_route_;
 	pathfind::paths current_paths_;
 	bool unselected_paths_;
+	bool unselected_reach_;
 	int path_turns_;
 	int side_num_;