Change `_can_handle` and `_edit` virtual methods to take `Object*`

doc/classes/EditorInspectorPlugin.xml

@@ -18,7 +18,7 @@
 	<methods>
 		<method name="_can_handle" qualifiers="virtual const">
 			<return type="bool" />
-			<param index="0" name="object" type="Variant" />
+			<param index="0" name="object" type="Object" />
 			<description>
 				Returns [code]true[/code] if this object can be handled by this plugin.
 			</description>

doc/classes/EditorPlugin.xml

@@ -38,7 +38,7 @@
 		</method>
 		<method name="_edit" qualifiers="virtual">
 			<return type="void" />
-			<param index="0" name="object" type="Variant" />
+			<param index="0" name="object" type="Object" />
 			<description>
 				This function is used for plugins that edit specific object types (nodes or resources). It requests the editor to edit the given object.
 				[param object] can be [code]null[/code] if the plugin was editing an object, but there is no longer any selected object handled by this plugin. It can be used to cleanup editing state.
@@ -295,7 +295,7 @@
 		</method>
 		<method name="_handles" qualifiers="virtual const">
 			<return type="bool" />
-			<param index="0" name="object" type="Variant" />
+			<param index="0" name="object" type="Object" />
 			<description>
 				Implement this function if your plugin edits a specific type of object (Resource or Node). If you return [code]true[/code], then you will get the functions [method _edit] and [method _make_visible] called when the editor requests them. If you have declared the methods [method _forward_canvas_gui_input] and [method _forward_3d_gui_input] these will be called too.
 			</description>

editor/editor_inspector.h

@@ -223,7 +223,7 @@ public:
 protected:
 	static void _bind_methods();
 
-	GDVIRTUAL1RC(bool, _can_handle, Variant)
+	GDVIRTUAL1RC(bool, _can_handle, Object *)
 	GDVIRTUAL1(_parse_begin, Object *)
 	GDVIRTUAL2(_parse_category, Object *, String)
 	GDVIRTUAL2(_parse_group, Object *, String)

editor/editor_plugin.cpp

@@ -662,11 +662,7 @@ void EditorPlugin::make_visible(bool p_visible) {
 }
 
 void EditorPlugin::edit(Object *p_object) {
-	if (Object::cast_to<Resource>(p_object)) {
-		GDVIRTUAL_CALL(_edit, Ref<Resource>(Object::cast_to<Resource>(p_object)));
-	} else {
-		GDVIRTUAL_CALL(_edit, p_object);
-	}
+	GDVIRTUAL_CALL(_edit, p_object);
 }
 
 bool EditorPlugin::handles(Object *p_object) const {

editor/editor_plugin.h

@@ -164,8 +164,8 @@ protected:
 	GDVIRTUAL0RC(Ref<Texture2D>, _get_plugin_icon)
 	GDVIRTUAL0RC(bool, _has_main_screen)
 	GDVIRTUAL1(_make_visible, bool)
-	GDVIRTUAL1(_edit, Variant)
-	GDVIRTUAL1RC(bool, _handles, Variant)
+	GDVIRTUAL1(_edit, Object *)
+	GDVIRTUAL1RC(bool, _handles, Object *)
 	GDVIRTUAL0RC(Dictionary, _get_state)
 	GDVIRTUAL1(_set_state, Dictionary)
 	GDVIRTUAL0(_clear)