Add a function in ExecUtils to return wall time and CPU time.

Bug: 245380798
Test: m test-art-host-gtest-art_runtime_tests
Change-Id: I25d0d4c3dfaf24490c96ca650f076b2214597d2a
Merged-In: I25d0d4c3dfaf24490c96ca650f076b2214597d2a
(cherry picked from commit ebbd20c55adbdde7922c2ca402e1a04ed6ecee4c)
4 files changed