[IC] Make SeededNumberDictionary::UpdateMaxNumberKey prototype aware

[IC] Make SeededNumberDictionary::UpdateMaxNumberKey prototype aware

Only walk the heap clearing KeyedStoreICs when the dictionary in question belongs to an object that's used as a prototype.
This is a temporary mitigation until we have a way to clear such ICs without having to walk the heap.

BUG=v8:4335
LOG=y
R=yangguo@chromium.org

Committed: https://crrev.com/df9822f45aec113e1f557de27c3b0f9e44a57cc4
Cr-Commit-Position: refs/heads/master@{#30076}

[Yang, 2015-08-07 21:28:50]

LGTM

https://codereview.chromium.org/1275363002/diff/1/src/objects.cc
File src/objects.cc (right):

https://codereview.chromium.org/1275363002/diff/1/src/objects.cc#newcode14647
src/objects.cc:14647: // TODO(verwaest): Remove this hack.
Indeed!

[Jakob Kummerow, 2015-08-07 22:09:41]

The CQ bit was checked by jkummerow@chromium.org

[commit-bot: I haz the power, 2015-08-07 22:09:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1275363002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1275363002/1

[commit-bot: I haz the power, 2015-08-07 22:45:01]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-08-07 22:45:24]

Patchset 1 (id:??) landed as
https://crrev.com/df9822f45aec113e1f557de27c3b0f9e44a57cc4
Cr-Commit-Position: refs/heads/master@{#30076}