crosperf: Fix bugs and nit in report generation

Fixed two parts in source code to make unit test pass:
1) Without unit, cpu cycles still should multiply by weight
2) Do not try to access cwp_dso from experiment in BenchmarkResult object,
   because there is method to generate report without running
   experiment.

One nit to change the name of TableGenerator used for CPU cycle report.

TEST=passed all unit tests in crosperf
BUG=chromium:902785
CQ-DEPEND=CL:1376571

Change-Id: I8308b0287d60e77542ac60f5ecd5734907e51e01
Reviewed-on: https://chromium-review.googlesource.com/1389035
Commit-Ready: Zhizhou Yang <zhizhouy@google.com>
Tested-by: Zhizhou Yang <zhizhouy@google.com>
Reviewed-by: Luis Lozano <llozano@chromium.org>
2 files changed