WorkSpace: UI filtering for add-ons

Allows for each workspace to have it's own add-ons on display.

Filtering for: Panels, Menus, Keymaps & Manipulators.
Automatically applies to add-ons at the moment.

Access from workspace, toggled off by default
once enabled, add-ons can be white-listed.

See D3076

source/blender/python/intern/bpy.c

@@ -376,6 +376,9 @@ void BPy_init_modules(void)
 	PyModule_AddObject(mod, meth_bpy_register_class.ml_name, (PyObject *)PyCFunction_New(&meth_bpy_register_class, NULL));
 	PyModule_AddObject(mod, meth_bpy_unregister_class.ml_name, (PyObject *)PyCFunction_New(&meth_bpy_unregister_class, NULL));
 
+	PyModule_AddObject(mod, meth_bpy_owner_id_get.ml_name, (PyObject *)PyCFunction_New(&meth_bpy_owner_id_get, NULL));
+	PyModule_AddObject(mod, meth_bpy_owner_id_set.ml_name, (PyObject *)PyCFunction_New(&meth_bpy_owner_id_set, NULL));
+
 	/* add our own modules dir, this is a python package */
 	bpy_package_py = bpy_import_test("bpy");
 }

source/blender/python/intern/bpy_rna.c

@@ -8257,6 +8257,43 @@ static PyObject *pyrna_unregister_class(PyObject *UNUSED(self), PyObject *py_cla
 	Py_RETURN_NONE;
 }
 
+/* Access to 'owner_id' internal global. */
+
+static PyObject *pyrna_bl_owner_id_get(PyObject *UNUSED(self))
+{
+	const char *name = RNA_struct_state_owner_get();
+	if (name) {
+		return PyUnicode_FromString(name);
+	}
+	Py_RETURN_NONE;
+}
+
+static PyObject *pyrna_bl_owner_id_set(PyObject *UNUSED(self), PyObject *value)
+{
+	const char *name;
+	if (value == Py_None) {
+		name = NULL;
+	}
+	else if (PyUnicode_Check(value)) {
+		name = _PyUnicode_AsString(value);
+	}
+	else {
+		PyErr_Format(PyExc_ValueError,
+		             "owner_set(...): "
+		             "expected None or a string, not '%.200s'", Py_TYPE(value)->tp_name);
+		return NULL;
+	}
+	RNA_struct_state_owner_set(name);
+	Py_RETURN_NONE;
+}
+
+PyMethodDef meth_bpy_owner_id_get = {
+	"_bl_owner_id_get", (PyCFunction)pyrna_bl_owner_id_get, METH_NOARGS, NULL,
+};
+PyMethodDef meth_bpy_owner_id_set = {
+	"_bl_owner_id_set", (PyCFunction)pyrna_bl_owner_id_set, METH_O, NULL,
+};
+
 /* currently this is fairly limited, we would need to make some way to split up
  * pyrna_callback_classmethod_... if we want more than one callback per type */
 typedef struct BPyRNA_CallBack {

source/blender/python/intern/bpy_rna.h

@@ -225,4 +225,8 @@ int pyrna_prop_validity_check(BPy_PropertyRNA *self);
 extern PyMethodDef meth_bpy_register_class;
 extern PyMethodDef meth_bpy_unregister_class;
 
+/* bpy.utils._bl_owner_(get/set) */
+extern PyMethodDef meth_bpy_owner_id_set;
+extern PyMethodDef meth_bpy_owner_id_get;
+
 #endif