Add some more bullet-proofing to the search results template.
Add some more bullet-proofing to the search results template.

Some people encounter a wacky bug whereby some of the search results have null
data, which results in an exception. This change adds some more bullet-proofing
to the template to try to skip bad results.

Testing done:
- Ran unit tests
- Generated a search index and did some searches.

Fixes(?) bug 3599.

Reviewed at https://reviews.reviewboard.org/r/6930/

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