fix bug #61860: use USearch for searches, it does the right thing
small optimization
Add a __wakeup() method to SplFixedArray, thereby fixing serialising an

SplFixedArray object and bug #60560 (SplFixedArray un-/serialize, getSize(),
count() return 0, keys are strings).
Merge branch 'bug61860' into PHP-5.4

* bug61860:
  small optimization
  fix bug #61860: use USearch for searches, it does the right thing