SurfaceFlinger and libgui: Support for child layers.
Add support for parenting Layers in a tree. Layers
follow scene-graph style rules, that is to say:
1. A child is cropped to the final bounds of the parent.
2. A child inherits the parent's transform (including position)
3. A child's Z ordering is relative to the parent and bounded between
the parents siblings.
4. A childs lifetime is bounded by it's parents lifetime.
Test: New tests in Transaction_test plus manual testing with later branches.
Change-Id: I96f8ad863665b9a70b6f845561344c297b7e6eff
16 files changed