ButtonCompat: handle missing StateListAnimator gracefully.

ButtonCompat: handle missing StateListAnimator gracefully.

ButtonCompat can crash on custom ROMs, when using a framework like Xposed, and
potentially on future versions of Android, because it assumes that the
Widget.Material.Button style contains a stateListAnimator attribute. This is
actually a dangerous assumption, since a future version of Android could change
Widget.Material.Button.

This CL handles this situation gracefully by simply not using a
StateListAnimator on the button if Widget.Material.Button doesn't contain a
stateListAnimator attribute.

BUG=525511
Committed: https://crrev.com/399439d551c3bd915fe180b8c0f3f8e0078623b5
Cr-Commit-Position: refs/heads/master@{#353454}

[newt (away), 2015-10-09 18:53:20]

newt@chromium.org changed reviewers:
+ aurimas@chromium.org

[newt (away), 2015-10-09 18:53:21]

PTAL

[aurimas (slooooooooow), 2015-10-10 00:46:38]

lgtm

[aurimas (slooooooooow), 2015-10-10 00:46:45]

The CQ bit was checked by aurimas@chromium.org

[commit-bot: I haz the power, 2015-10-10 00:47:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1390883007/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1390883007/1

[commit-bot: I haz the power, 2015-10-10 02:09:06]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-10-10 02:09:49]

Patchset 1 (id:??) landed as
https://crrev.com/399439d551c3bd915fe180b8c0f3f8e0078623b5
Cr-Commit-Position: refs/heads/master@{#353454}