getLink() used to consider the whole enclosed text content, now it only looks at the directly contained text

[wosc]

Here's another of those mechanize-to-webtest compatibility issues:

<a href="..."><span>My link</span></a> used to be findable with browser.getLink('My link'), since mechanize collects all nested text, but now it's not found anymore, since zope.testbrowser only looks at the directly contained text.