Add IME support checks in LineEdit/TextEdit.

Avoid spamming "IME is unsupported" when the DisplayServer report it as
such.

scene/gui/line_edit.cpp

@@ -848,7 +848,7 @@ void LineEdit::_notification(int p_what) {
 			}
 
 			if (has_focus()) {
-				if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID) {
+				if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID && DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_IME)) {
 					DisplayServer::get_singleton()->window_set_ime_active(true, get_viewport()->get_window_id());
 					DisplayServer::get_singleton()->window_set_ime_position(get_global_position() + Point2(using_placeholder ? 0 : x_ofs, y_ofs + TS->shaped_text_get_size(text_rid).y), get_viewport()->get_window_id());
 				}
@@ -865,7 +865,7 @@ void LineEdit::_notification(int p_what) {
 				}
 			}
 
-			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID) {
+			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID && DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_IME)) {
 				DisplayServer::get_singleton()->window_set_ime_active(true, get_viewport()->get_window_id());
 				Point2 cursor_pos = Point2(get_cursor_position(), 1) * get_minimum_size().height;
 				DisplayServer::get_singleton()->window_set_ime_position(get_global_position() + cursor_pos, get_viewport()->get_window_id());
@@ -878,7 +878,7 @@ void LineEdit::_notification(int p_what) {
 				caret_blink_timer->stop();
 			}
 
-			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID) {
+			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID && DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_IME)) {
 				DisplayServer::get_singleton()->window_set_ime_position(Point2(), get_viewport()->get_window_id());
 				DisplayServer::get_singleton()->window_set_ime_active(false, get_viewport()->get_window_id());
 			}

scene/gui/text_edit.cpp

@@ -1702,7 +1702,7 @@ void TextEdit::_notification(int p_what) {
 			}
 
 			if (has_focus()) {
-				if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID) {
+				if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID && DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_IME)) {
 					DisplayServer::get_singleton()->window_set_ime_active(true, get_viewport()->get_window_id());
 					DisplayServer::get_singleton()->window_set_ime_position(get_global_position() + cursor_pos, get_viewport()->get_window_id());
 				}
@@ -1715,7 +1715,7 @@ void TextEdit::_notification(int p_what) {
 				draw_caret = true;
 			}
 
-			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID) {
+			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID && DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_IME)) {
 				DisplayServer::get_singleton()->window_set_ime_active(true, get_viewport()->get_window_id());
 				DisplayServer::get_singleton()->window_set_ime_position(get_global_position() + _get_cursor_pixel_pos(false), get_viewport()->get_window_id());
 			}
@@ -1744,7 +1744,7 @@ void TextEdit::_notification(int p_what) {
 				caret_blink_timer->stop();
 			}
 
-			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID) {
+			if (get_viewport()->get_window_id() != DisplayServer::INVALID_WINDOW_ID && DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_IME)) {
 				DisplayServer::get_singleton()->window_set_ime_position(Point2(), get_viewport()->get_window_id());
 				DisplayServer::get_singleton()->window_set_ime_active(false, get_viewport()->get_window_id());
 			}