Revert "Write dex files to oat file early."

This reverts commit 625a64aad13905d8a2454bf3cc0e874487b110d5.

Breaks the Mac build:

Undefined symbols for architecture i386:
  "_CloseArchive", referenced from:
      ... in oat_writer.o
ld: symbol(s) not found for architecture i386

Change-Id: I21608bc51437834e1e6abde9bcbe5e7d9998197e
19 files changed