Currently, it only contains ART boot image related information, i.e.
.art, .oat and .vdex files. However, follow up changes will extend that
to include other information from bootclasspath_fragment.
Bug: 177892522
Test: m nothing
Change-Id: I2b226131c0eccff0c739a18f265f90caa10a91d9
Also renames files, tests, module types in a similar fashion.
There are still some references to image and boot image. They are kept
for the following reasons:
* image_name - this is the name of an ART boot image, i.e. the
collection of .art/.oat/.vdex files.
* BootImageInfo - again this is related to the ART boot image.
* .../art_boot_images/... paths - ditto.
Bug: 177892522
Test: m nothing
Change-Id: Ie1f4738061d131fee75de48bc26a7601481bad4d
