Handle permission page URI for each app something like "settings://com.website.app"

[ryonakano]

Subtask for elementary/granite#914

[ryonakano]

Currently, System Settings handles settings:// URI here (after stripping settings:// itself):

settings/src/Application.vala

Lines 230 to 252 in 6cc9b7d

	// Try to find a supported plug, fallback paths like "foo/bar" to "foo"
	public bool load_setting_path (string setting_path, Switchboard.PlugsManager plugsmanager) {
	foreach (var plug in plugsmanager.get_plugs ()) {
	var supported_settings = plug.supported_settings;
	if (supported_settings == null) {
	continue;
	}
	if (supported_settings.has_key (setting_path)) {
	load_plug (plug);
	open_window = supported_settings.get (setting_path);
	return true;
	}
	}
	// Fallback to subpath
	if ("/" in setting_path) {
	int last_index = setting_path.last_index_of_char ('/');
	return load_setting_path (setting_path.substring (0, last_index), plugsmanager);
	}
	return false;
	}

However, it assumes all settings:// URI is defined statically in each Plug and does not consider it changes dynamically (e.g. by installing/uninstalling apps), so maybe we need to modify how to load URI to archive the parent task?

[ryonakano]

Ah possibly, adding some prefix like settings://apps/com.website.app, then handling settings://apps/ URI in settings-applications could work. settings-applications is responsible for checking if com.website.app is installed and possibly show some AlertView if not installed.