Switch to HexEncoding from ByteStringUtils

Migration in preparation for deletion of ByteStringUtils.

DexLogger contains import ordering fixes to enable upload.

Bug: 124232146
Test: build only
Exempt-From-Owner-Approval: Already approved internally
Merged-In: I2cb09da5ec5296799e03bab812b7fb29452a623e
Change-Id: I2cb09da5ec5296799e03bab812b7fb29452a623e