Fix Dartium DEBUG failures by ensuring proper scoping within GC prologue/epilogue.

Fix Dartium DEBUG failures by ensuring proper scoping within GC prologue/epilogue.

This ensures that the zone-allocating parts of ScavengeVisitor and MarkingVisitor are destroyed before the Dartium GC epilogue deletes the zone in which they were allocating.

(This only explains DEBUG mode failures, caused by the zapping in the GrowableArray destructor, because the values of the arrays are not used after the epilogue runs.)

BUG=dart:22224
R=asiva@google.com

Committed: https://code.google.com/p/dart/source/detail?r=43558

[siva, 2015-02-05 23:53:07]

LGTM.

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/gc_marker.cc
File runtime/vm/gc_marker.cc (right):

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/gc_marker.cc#...
runtime/vm/gc_marker.cc:508: {
maybe we should start our own zone here.

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/scavenger.cc
File runtime/vm/scavenger.cc (right):

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/scavenger.cc#...
runtime/vm/scavenger.cc:823: {
Ditto comment.

[koda, 2015-02-06 00:14:16]

New patchsets have been uploaded after l-g-t-m from asiva@google.com

[koda, 2015-02-06 00:16:07]

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/gc_marker.cc
File runtime/vm/gc_marker.cc (right):

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/gc_marker.cc#...
runtime/vm/gc_marker.cc:508: {
On 2015/02/05 23:53:06, siva wrote:
> maybe we should start our own zone here.

Done.

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/scavenger.cc
File runtime/vm/scavenger.cc (right):

https://codereview.chromium.org/896133003/diff/40002/runtime/vm/scavenger.cc#...
runtime/vm/scavenger.cc:823: {
On 2015/02/05 23:53:06, siva wrote:
> Ditto comment.

Done.

[koda, 2015-02-06 17:38:45]

Committed patchset #6 (id:80001) manually as r43558 (presubmit successful).