SVG: Add comment to |loopbreaker| local static var that it is safe

SVG: Add comment to |loopbreaker| local static var that it is safe

This is a follow up CL to https://codereview.chromium.org/305783004/

BUG=357163
NOTRY=true

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=175093

[kouhei (in TOK), 2014-05-30 01:38:07]

rubberstamp plz

[haraken, 2014-05-30 01:39:45]

LGTM

https://codereview.chromium.org/308793003/diff/1/Source/core/svg/animation/SV...
File Source/core/svg/animation/SVGSMILElement.cpp (right):

https://codereview.chromium.org/308793003/diff/1/Source/core/svg/animation/SV...
Source/core/svg/animation/SVGSMILElement.cpp:1250: // |loopbreaker| is used to
avoid infinite recursions which may be caused from:

loopBreaker

https://codereview.chromium.org/308793003/diff/1/Source/core/svg/animation/SV...
Source/core/svg/animation/SVGSMILElement.cpp:1252: // |loopbreaker| is defined
as a Persistent<HeapHashSet<Member<SVGSMILElement> > >. This is safe because it
is guaranteed to be empty after the root |notifyDependentsIntervalChanged| has
exit.

this is safe => this won't cause leaks
has exit => has exited

[kouhei (in TOK), 2014-05-30 01:51:38]

The CQ bit was checked by kouhei@chromium.org

[commit-bot: I haz the power, 2014-05-30 01:53:00]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/kouhei@chromium.org/308793003/20001

[commit-bot: I haz the power, 2014-05-30 01:53:57]

Change committed as 175093