Introduce partial code cache collection.

It will collect code that is known unused (because it deoptimized),
and osr code.

bug:26846185

(cherry picked from commit 8d37250f7b9a7839b11488f45a1842b025026f94)

Change-Id: Iffe87e356066a3f0bd28cb3df41c17bf2ac9ea0f
2 files changed