commit 8aa9959413a06c3d2ff75e0c7be9e3cb7ac7cd2e
author Winson <winsonc@google.com> Tue Jan 19 15:07:07 2016 -0800
committer Winson <winsonc@google.com> Thu Jan 21 16:05:53 2016 -0800
tree c81e6d47c775077896ea981069e59269ba1dff1d
parent b7a73360b50ede90b4331dd041eef59f002dc131

Starting the dismiss animation in parallel with the gesture.

- Introduces notion of ignored tasks for the purposes of layout in 
  TaskStackView.  This can be used during drag and drop, and while 
  dismissing to calculate the state of the stack without the task that
  the user is currently interacting with.
- Fixing minor layout issue when the front/back task transforms are 
  improperly calculated when there is a single task
- Fixing minor issue when the anchor task is calculated incorrectly when
  dismissing task views

Change-Id: I1eb0864a52e53562e4d573a6ed4f8a5a1615aff9