Fix error in RenderNode unit test with Skia pipeline

Fix failing RenderNode unit tests with Skia pipeline, caused by
TestUtils::syncHierarchyPropertiesAndDisplayList not walking past
root node.

Test: ran HWUI unit tests.
bug: 32507847
Change-Id: I7e64fb02fd8f4874eadacafcac7e9f1ae4e56365
1 file changed