Improved exception when a type hint class can not be found

[arnaud-lb]

This improves the exception message when a type hint class was not found during the generation of a proxy.

Example:

<?php
class Foo
{
    function test(\InvalidClass $param) 
    {
    }
}

When generating a proxy for this class Foo, if the type hint class InvalidClass cannot be found, a ReflectionException exception is thrown with the following message: Class InvalidClass does not exist. There is no hint on the real cause of the error (which class, method, ...).

This PR wraps this exception with a message making the cause of the exception more obvious.

[doctrinebot]

Hello,

thank you for positing this Pull Request. I have automatically opened an issue on our Jira Bug Tracker for you with the details of this Pull-Request. See the Link:

http://doctrine-project.org/jira/browse/DDC-2145

[doctrinebot]

Oh btw, I just (automatically) realized that you are not creating this pull request against the master branch.

Unless there are good reasons for this, i would suggest to close and rebase the Pull Request against master and then create it again. Sorry!

[arnaud-lb]

closing because duplicate of PR 469