Default Fallback with Lateral Fallback

[Fae-Bell]

Hello,
I'm seeing two, maybe related, issues with Sitecore 7.2 Update 2.

1. Lateral fallback doesn't work off of a default field value. We're attempting to set the Breadcrumbs to the Navigation Title and have the Navigation Title based off of the $name. Breadcrumbs was not updating properly, but when I modified Navigation Title it updated to the new, non-fallback, value.
2. For the same example, there is an odd bug where the Breadcrumbs are being seen as falling back on the Default Field Processor (Believed to have been modified, saved, then removed) even though it's empty. I was able to modify the pipeline to have Literal appear before default in an attempt to fix this issue, which is how I ran into the first issue.

[Fae-Bell]

I found that the main issue is that a lot of the checks for if a field has a value is "value == null" rather than "string.IsNullOrEmpty(value)" -- I pulled the code down and tried the above fix and it worked as expected. I found that this happens with most of the processors.

[seankearney]

Keith,
The null checks were intentionally made as the string.IsNullOrEmpty check isn't what was desired. This is inline with normal Sitecore and 'Standard Value' behavior. If an editor specified an empty string in a field then that trumps a null value from the standard value. In that case the field needs to be reset.

[Fae-Bell]

We were seeing issues in which it was taking the value from the Default Fallback even though that field was never touched. It was trumping another field because the returned value was an empty string rather than a null.

[hhog-tkamin]

Updated the documentation to provide better information on having Lateral Fallback work on nested fallback.