[462884] Refactor MergeAllNonConflictingRunnable & MergeDependenciesUtil

This refactoring prepares the use of MergeAllNonConflictingRunnable for
handling also mergings of contained non-conflicting differences.

Bug: 462884
Change-Id: I9be5ed3b5aa38c98bd3ab2b7abf42cedd7396cf8
Signed-off-by: Philip Langer <planger@eclipsesource.com>
3 files changed