Fix recursive Tree expand/collapse shortcuts not working

This also moves them to use Shift instead of Alt, as was already
done for mouse interactions.

Shortcuts in Tree were also made non-exact matches so they still
work if modifiers are held. This is important for up/down
shortcuts, especially once support for selecting with
Shift + up/down is implemented.

doc/classes/Tree.xml

@@ -353,7 +353,7 @@
 			This controls the drop sections, i.e. the decision and drawing of possible drop locations based on the mouse position.
 		</member>
 		<member name="enable_recursive_folding" type="bool" setter="set_enable_recursive_folding" getter="is_recursive_folding_enabled" default="true">
-			If [code]true[/code], recursive folding is enabled for this [Tree]. Holding down Shift while clicking the fold arrow collapses or uncollapses the [TreeItem] and all its descendants.
+			If [code]true[/code], recursive folding is enabled for this [Tree]. Holding down [kbd]Shift[/kbd] while clicking the fold arrow or using [code]ui_right[/code]/[code]ui_left[/code] shortcuts collapses or uncollapses the [TreeItem] and all its descendants.
 		</member>
 		<member name="focus_mode" type="int" setter="set_focus_mode" getter="get_focus_mode" overrides="Control" enum="Control.FocusMode" default="2" />
 		<member name="hide_folding" type="bool" setter="set_hide_folding" getter="is_folding_hidden" default="false">

scene/gui/tree.cpp

@@ -3394,7 +3394,7 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 	Ref<InputEventKey> k = p_event;
 
 	bool is_command = k.is_valid() && k->is_command_or_control_pressed();
-	if (p_event->is_action("ui_right", true) && p_event->is_pressed()) {
+	if (p_event->is_action("ui_right") && p_event->is_pressed()) {
 		if (!cursor_can_exit_tree) {
 			accept_event();
 		}
@@ -3402,17 +3402,12 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 		if (!selected_item || select_mode == SELECT_ROW || selected_col > (columns.size() - 1)) {
 			return;
 		}
-		if (k.is_valid() && k->is_alt_pressed()) {
-			selected_item->set_collapsed(false);
-			TreeItem *next = selected_item->get_first_child();
-			while (next && next != selected_item->next) {
-				next->set_collapsed(false);
-				next = next->get_next_visible();
-			}
+		if (k.is_valid() && k->is_shift_pressed()) {
+			selected_item->set_collapsed_recursive(false);
 		} else {
 			_go_right();
 		}
-	} else if (p_event->is_action("ui_left", true) && p_event->is_pressed()) {
+	} else if (p_event->is_action("ui_left") && p_event->is_pressed()) {
 		if (!cursor_can_exit_tree) {
 			accept_event();
 		}
@@ -3421,32 +3416,27 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 			return;
 		}
 
-		if (k.is_valid() && k->is_alt_pressed()) {
-			selected_item->set_collapsed(true);
-			TreeItem *next = selected_item->get_first_child();
-			while (next && next != selected_item->next) {
-				next->set_collapsed(true);
-				next = next->get_next_visible();
-			}
+		if (k.is_valid() && k->is_shift_pressed()) {
+			selected_item->set_collapsed_recursive(true);
 		} else {
 			_go_left();
 		}
 
-	} else if (p_event->is_action("ui_up", true) && p_event->is_pressed() && !is_command) {
+	} else if (p_event->is_action("ui_up") && p_event->is_pressed() && !is_command) {
 		if (!cursor_can_exit_tree) {
 			accept_event();
 		}
 
 		_go_up();
 
-	} else if (p_event->is_action("ui_down", true) && p_event->is_pressed() && !is_command) {
+	} else if (p_event->is_action("ui_down") && p_event->is_pressed() && !is_command) {
 		if (!cursor_can_exit_tree) {
 			accept_event();
 		}
 
 		_go_down();
 
-	} else if (p_event->is_action("ui_page_down", true) && p_event->is_pressed()) {
+	} else if (p_event->is_action("ui_page_down") && p_event->is_pressed()) {
 		if (!cursor_can_exit_tree) {
 			accept_event();
 		}
@@ -3484,7 +3474,7 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 		}
 
 		ensure_cursor_is_visible();
-	} else if (p_event->is_action("ui_page_up", true) && p_event->is_pressed()) {
+	} else if (p_event->is_action("ui_page_up") && p_event->is_pressed()) {
 		if (!cursor_can_exit_tree) {
 			accept_event();
 		}
@@ -3521,7 +3511,7 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 			prev->select(selected_col);
 		}
 		ensure_cursor_is_visible();
-	} else if (p_event->is_action("ui_accept", true) && p_event->is_pressed()) {
+	} else if (p_event->is_action("ui_accept") && p_event->is_pressed()) {
 		if (selected_item) {
 			//bring up editor if possible
 			if (!edit_selected()) {
@@ -3530,7 +3520,7 @@ void Tree::gui_input(const Ref<InputEvent> &p_event) {
 			}
 		}
 		accept_event();
-	} else if (p_event->is_action("ui_select", true) && p_event->is_pressed()) {
+	} else if (p_event->is_action("ui_select") && p_event->is_pressed()) {
 		if (select_mode == SELECT_MULTI) {
 			if (!selected_item) {
 				return;