Fatal error exporting contributions with campaigns, if campaign name > 16 chars

To replicate:

• Create a campaign and name it "test campaign 1234567" (longer than 16 chars)
• Create a contribution assigned to that campaign
• Search for that contribution
• Select that contribution and export it.
  You'll get a DB error like the one attached.
  The problem is that the campaign ID column in the export is being populated with the campaign name, and the campaign name column is left empty.

Tested on drupal.demo.civicrm.org