Reduce Maniphest fulltext limit from PHP_INT_MAX to 10k

Summary:
PHP_INT_MAX is rejected by ElasticSearch since it's outside of the representable integer range (see: <https://gist.github.com/JustinTulloss/c4ac0e1c93d6d1e91744>).

Just use 10K, as matching more than 10K results probably isn't useful to anyone.

Test Plan: Confirmed this fixes the issue in IRC. Ran a fulltext search.

Reviewers: btrahan

Reviewed By: btrahan

CC: aran

Differential Revision: https://secure.phabricator.com/D7097

src/applications/maniphest/query/ManiphestTaskQuery.php

@@ -482,7 +482,10 @@ final class ManiphestTaskQuery
     // fulltext search, and then use that to limit the rest of the search
     $fulltext_query = new PhabricatorSearchQuery();
     $fulltext_query->setQuery($this->fullTextSearch);
-    $fulltext_query->setParameter('limit', PHP_INT_MAX);
+
+    // NOTE: Setting this to something larger than 2^53 will raise errors in
+    // ElasticSearch, and billions of results won't fit in memory anyway.
+    $fulltext_query->setParameter('limit', 100000);
     $fulltext_query->setParameter('type', ManiphestPHIDTypeTask::TYPECONST);
 
     $engine = PhabricatorSearchEngineSelector::newSelector()->newEngine();