tree c2316bc7347563bd7c22c67c5b6705c39a92f089
parent ae0608381b2b4699218febd6d45ad9d307544d55
author Robert Carr <racarr@google.com> 1480370949 -0800
committer Robert Carr <racarr@google.com> 1485291484 -0800

SurfaceFlinger: Use traversal functions to iterate LayerList.

In preparation for the Layer hierarchy. There we will need
to use such a style to traverse the tree of layers.

Test: Just a refactoring. SurfaceFlinger still works.
Change-Id: I84dcd82e713f1bdbe911658793ce11460267a956