Exception in return from 'getToolVisibility' if the tool is not found for a session

[juancp-contidosdixitais]

It is possible to have sessions in which the visibility of the 'document' tool (or any other) is not set in the c_tool table. However, there will still be a record for the base course, allowing the session to inherit this configuration without specifically creating a new record in that table. This approach works in most use cases.

However, with the CKEditor File Manager, we might encounter a problem. In course_home.lib.php.getToolVisibility($toolName, $courseId, $sessionId = 0), an exception could be thrown when opening the File Manager. This is because it checks for the 'document' tool's visibility for the session, but the $visibility variable is not initialized unless there is a corresponding record for the session in the c_tool table

chamilo-lms/main/inc/lib/course_home.lib.php

Lines 1868 to 1873 in 400f7a4

	if ($tool) {
	$visibility = $tool->getVisibility();
	}
	return $visibility;

This pull request fixes this issue by initializing the $visibility variable to false right before the if statement