Make profile inline cache threshold configurable.

After this change, the profile inline cache threshold is configurable
through a system property "dalvik.vm.ps-inline-cache-threshold".

Bug: 309434431
Test: Set "dalvik.vm.ps-inline-cache-threshold" to different values, run
  a compose app benchmark, dump the profile, and see the difference in
  the profiles.
Change-Id: Ie430d8d21e2d4af92385b244bf327900b9c14d93