Decrease the editor FPS limit when unfocused from 20 to 10

This provides better power savings compared to the previous value.
This also speeds up project execution slightly while the editor
is running in the background.

The setting hint can now go as low as 1 FPS (1 million microseconds
per frame), for those who really need the best possible power savings.
This will make previewing animated shaders or particles impossible
when the editor window isn't focused though.

(cherry picked from commit 6f6a09cce203dccb493d4d7a8d42ab860444dcc2)

editor/editor_settings.cpp

@@ -333,8 +333,12 @@ void EditorSettings::_load_defaults(Ref<ConfigFile> p_extra_config) {
 	_initial_set("interface/editor/dim_editor_on_dialog_popup", true);
 	_initial_set("interface/editor/low_processor_mode_sleep_usec", 6900); // ~144 FPS
 	hints["interface/editor/low_processor_mode_sleep_usec"] = PropertyInfo(Variant::REAL, "interface/editor/low_processor_mode_sleep_usec", PROPERTY_HINT_RANGE, "1,100000,1", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
-	_initial_set("interface/editor/unfocused_low_processor_mode_sleep_usec", 50000); // 20 FPS
-	hints["interface/editor/unfocused_low_processor_mode_sleep_usec"] = PropertyInfo(Variant::REAL, "interface/editor/unfocused_low_processor_mode_sleep_usec", PROPERTY_HINT_RANGE, "1,100000,1", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
+	_initial_set("interface/editor/unfocused_low_processor_mode_sleep_usec", 100000); // 10 FPS
+	// Allow an unfocused FPS limit as low as 1 FPS for those who really need low power usage
+	// (but don't need to preview particles or shaders while the editor is unfocused).
+	// With very low FPS limits, the editor can take a small while to become usable after being focused again,
+	// so this should be used at the user's discretion.
+	hints["interface/editor/unfocused_low_processor_mode_sleep_usec"] = PropertyInfo(Variant::REAL, "interface/editor/unfocused_low_processor_mode_sleep_usec", PROPERTY_HINT_RANGE, "1,1000000,1", PROPERTY_USAGE_DEFAULT | PROPERTY_USAGE_RESTART_IF_CHANGED);
 	_initial_set("interface/editor/separate_distraction_mode", false);
 	_initial_set("interface/editor/automatically_open_screenshots", true);
 	_initial_set("interface/editor/hide_console_window", false);