cc: Change Layer::PushProps conditional to say what it means

cc: Change Layer::PushProps conditional to say what it means

This conditional really only applies when property trees are being used,
even though currently impl-side painting and property trees are
synonymous.
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Committed: https://crrev.com/a570aa307530d83f610b6c5bd91e3117347ed15f
Cr-Commit-Position: refs/heads/master@{#332962}

[enne (OOO), 2015-06-04 21:31:18]

enne@chromium.org changed reviewers:
+ vollick@chromium.org

[Ian Vollick, 2015-06-04 21:35:11]

lgtm

[enne (OOO), 2015-06-04 21:42:56]

The CQ bit was checked by enne@chromium.org

[commit-bot: I haz the power, 2015-06-04 21:43:45]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1166613003/1

[commit-bot: I haz the power, 2015-06-04 22:05:07]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-06-04 22:05:08]

Try jobs failed on following builders:
  android_chromium_gn_compile_rel on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/android_chromiu...)

[enne (OOO), 2015-06-04 22:08:54]

The CQ bit was checked by enne@chromium.org

[commit-bot: I haz the power, 2015-06-04 22:10:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1166613003/1

[commit-bot: I haz the power, 2015-06-04 23:41:37]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-04 23:42:40]

Patchset 1 (id:??) landed as
https://crrev.com/a570aa307530d83f610b6c5bd91e3117347ed15f
Cr-Commit-Position: refs/heads/master@{#332962}