Fix ProcessRecord losing track of its own render thread tid

As part of ag/33615448, which is aimed at improving app launch performance, we set and boost the render thread priority (by calling setRenderThread()) as soon as possible after starting preloading the graphics library context. This has resulted in a scenario where sometimes, a ProcessRecord would no longer have a correct render thread tid set (for a specific example, check the bug linked below). This was because the HardwareRenderer.initSched() method was no longer called by HardwareRenderer.init(). Reverting now the part where initSched was no longer being called.

Tested the change by Perfetto tracing the CUJ that highlighted this issue and it now works as intended.

Flag: EXEMPT bugfix
Bug: 424367455
Change-Id: I79179f3288ffa6f62487e94689dcfd7a156b7b52