Remove implementation of global transaction

Since I67e4e58aced78a2f36163178a64ca55d3c77e6f3, the methods of
global transaction have no effective use case anymore.

Keep the empty method openTransaction and closeTransaction because
scrcpy might still use reflection to check the methods. However, it is
safe to make these 2 method no-op because setDisplaySurface,
setDisplayProjection, and setDisplayLayerStack no longer use global
transaction. See [1] and [2].

[1]: I859743cb8b10c0352a30280a610b13a4f44f34dc
[2]: I8ea8b26f4f5f8e7675a8a9fcf06c7f10cfa9e196

Bug: 159103089
Test: presubmit
Change-Id: If38dfbe77d0be12bceb5e75600f486a53c9cd2c6