Throw OutOfMemoryError on oversize array allocs.

Throw OutOfMemoryError on oversize array allocs.

We've been throwing InternalError because of a particular statement in
the JPL that suggests we should be clearing out SoftReferences before
throwing OOM.  That seems unnecessary for an array allocation that we're
rejecting because the total size doesn't fit in a 32-bit integer.

Now we just throw OOM.