Revert "Log when duplicate elements are first added to DexPathList."

This reverts commit a599c6c5.

Reason for revert: The logging involves overhead for app startup that we don't want to carry in P Beta 2.

Note: this revert involved a minor merge conflict resolution because
 the revert removed the import of java.util.Set which conflicts with
 commit e81130c4 adding the import of
 java.util.Objects

Test: Treehugger
Bug: 77342775
Change-Id: I50c8c39abe27ebd23138e327970adbabba3e2ecc