Disable app image for very large apps

App images prevent dex2oat unloading and should not be used in this
mode. Disable app image generation when very large app mode is
detected.

Bug: 63467744
Test: test-art-host-gtest-dex2oat_test

(cherry picked from commit df8a96a1)

Change-Id: Icd5b0d9d3e61ececffe60f7472aaee8a54d1847b