Enable compiling dex files in isolation on low ram devices.

It takes longer but reduces the memory footprint.

Test: adb install
Bug: 190277710
Merged-In: I42d24cfb2e965e440d7595da4c2e4ef7e97c0f23
Change-Id: I42d24cfb2e965e440d7595da4c2e4ef7e97c0f23
(cherry picked from commit 380fff71)