Reland "Change well known `ClassLoader` fields to `ArtField*`."

This reverts commit 839193ee2031d28aac2ce16c4b76ad40531b07cc.

Reason for revert: Reland with a fix - make CompilerDriver
reponsible for initializing required `ClassLoader` classes
for boot image.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Test: Manually run Golem benchmark ArrayListStress.
Bug: 253570082
Change-Id: I2ddb70566352f8728f089b3a6c58473270240e25