simpleperf: fix record file writer.

When running `run-as [package_name] ./simpleperf record...` on device,
simpleperf doesn't have permission to create temporary file in
/data/local/tmp. So create temporary files in the same directory
as perf.data instead.

Bug: http://b/30649868
Change-Id: I48178d4eb421be8d8636721ac3b29b98fa673b5d
Test: run simpleperf_unit_test.
1 file changed