simpleperf: remove RecordCache.

When using debug-unwind cmd for system wide profiling result, I
found it might took a lot of memory because RecordCache cached
too many samples. Since simpleperf no longer relies on RecordCache
to sort records, I think it is fine to remove RecordCache instead
of fixing it.

Bug: none.
Test: run simpleperf_unit_test.
Change-Id: Ie28ce17b4158add455004a56bbdac745f9d05f19
10 files changed