Move javac_wrapper.sh scripts into own files. am: 9de71a4e46

Original change: https://android-review.googlesource.com/c/platform/art/+/2057472

Change-Id: Ic16b5c61e5deb165a73fa720284995d3ce43cf13
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>