Fix LineEdit not consuming events

The most important issue is LineEdit not consuming
"ui_text_submit" event which makes pressing Enter after
editing escape to other components causing unwanted
interactions.

Also fix handling mouse button interactions not consuming
some events.

Also implement early return in case we know which event
type it is and there is no point in checking other event
types.

PS I'm also suspicious that mouse motion events also need
to be consumed, but haven't explored those cases.

scene/gui/line_edit.cpp

@@ -272,6 +272,7 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 				}
 			}
 			grab_focus();
+			accept_event();
 			return;
 		}
 
@@ -381,6 +382,7 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 		}
 
 		queue_redraw();
+		return;
 	}
 
 	Ref<InputEventMouseMotion> m = p_event;
@@ -405,6 +407,8 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 			drag_caret_force_displayed = true;
 			set_caret_at_pixel_pos(m->get_position().x);
 		}
+
+		return;
 	}
 
 	Ref<InputEventKey> k = p_event;
@@ -458,6 +462,9 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 				menu->reset_size();
 				menu->popup();
 				menu->grab_focus();
+
+				accept_event();
+				return;
 			}
 		}
 
@@ -467,6 +474,8 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 			if (DisplayServer::get_singleton()->has_feature(DisplayServer::FEATURE_VIRTUAL_KEYBOARD) && virtual_keyboard_enabled) {
 				DisplayServer::get_singleton()->virtual_keyboard_hide();
 			}
+			accept_event();
+			return;
 		}
 
 		if (is_shortcut_keys_enabled()) {
@@ -606,6 +615,7 @@ void LineEdit::gui_input(const Ref<InputEvent> &p_event) {
 				_text_changed();
 			}
 			accept_event();
+			return;
 		}
 	}
 }