GetInlinedDataUninitialized() is removed. Just use GetInlinedData() in
all cases instead. GetInlinedData() is sometimes used to return
uninitialized memory.  In these cases it is immediately constructed.

This is a followup to 511ad649. See also:
https://clang.llvm.org/docs/ControlFlowIntegrity.html#bad-cast-checking.

PiperOrigin-RevId: 551205766
Change-Id: I4ddb45e29a723ccf6fc7dc203e762f4ad559fc83