CE: Functional test for Display::postFramebuffer

Verify that DisplaySurface::onFrameCommitted() is called after
HWComposer::presentAndGetReleaseFences() when a framebuffer is posted to
the display.

Bug: 144116961
Test: atest libcompositionengine_test
Change-Id: I29928fac37771b4efa320a0140ab0f948f01ea89