RFR: Should return zero actual allocated size when allocation failed

[Aleksey Shipilev]

On 06/14/2018 10:02 PM, Zhengyu Gu wrote:
> Several of vmTestbase gc tests failed due to following assertion:
> 
> #  Internal Error
> (/home/zgu/workspace/shenandoah-jdk/src/hotspot/share/gc/shared/collectedHeap.cpp:407), pid=2985,
> tid=3045
> #  assert(actual_tlab_size == 0) failed: Allocation failed, but actual size was updated. min: 256,
> desired: 257, actual: 257
> 
> cause we return requested size even when allocation failed.
> 
> http://cr.openjdk.java.net/~zgu/shenandoah/new_tlab_size/webrev.00/

Looks good.

-Aleksey