Revert "Reland change to enable deferred image decoding for animated GIFs"

Lots of image diffs showed up on http://test-results.appspot.com/dashboards/flakiness_dashboard.html#tests=virtual%2Fdeferred%2Ffast%2Fimages%2Fwebp-color-profile-lossy.html

This reverts commit 4110425f5132d8d6f94395799c2d901068e38f6e.

TBR=hclam@chromium.org
BUG=169377,259786,259783

Review URL: https://codereview.chromium.org/19504009

git-svn-id: svn://svn.chromium.org/blink/trunk@154576 bbb929c8-8fbe-4397-9dbb-9b2b20218538