RFR(S): 8011771: runThese crashed with EAV

[Roland Westrelin]

http://cr.openjdk.java.net/~roland/8011771/webrev.00/

During in block motion, a step of array bound check elimination, the code doesn't always reset its data structures correctly when it moves from one array to another (it does when optimistic optimizations are on, not otherwise). As a result, some bound checks are incorrectly optimized out.

Roland.