During ai turn, do highlight the hex where the unit moved from

(consistent with multiplayer).

The unit being moved is still shown in the sidebar.

src/ai.cpp

@@ -416,7 +416,8 @@ gamemap::location ai_interface::move_unit_partial(location from, location to,
 	// Stop the user from issuing any commands while the unit is moving.
 	const events::command_disabler disable_commands;
 
-	info_.disp.select_hex(from);
+	// show the unit in the sidebar without highlighting it
+	info_.disp.display_unit_hex(from);
 	info_.disp.update_display();
 
 	log_scope2(ai, "move_unit");

src/game_display.cpp

@@ -238,6 +238,14 @@ void game_display::highlight_hex(gamemap::location hex)
 }
 
 
+void game_display::display_unit_hex(gamemap::location hex)
+{
+	if (units_.count(hex)) {
+		displayedUnitHex_ = hex;
+		invalidate_unit();
+	}
+}
+
 void game_display::invalidate_unit_after_move(const gamemap::location& src, const gamemap::location& dst)
 {
 	if (src == displayedUnitHex_) {

src/game_display.hpp

@@ -75,6 +75,10 @@ public:
 	//! while highlighting is used when a location has been moused over.
 	virtual void highlight_hex(gamemap::location hex);
 
+	//! Change the unit to be displayed in the sidebar.
+	//! This is used when selecting or highlighting is not wanted.
+	void display_unit_hex(gamemap::location hex);
+
 	//! Sets the paths that are currently displayed as available
 	//! for the unit to move along.
 	//! All other paths will be greyed out.