Merge branch 'gitlab-git-duplicate-code' into 'master'

Remove duplicate method definitions

See merge request gitlab-org/gitlab-ce!17478

lib/gitlab/git/repository.rb

@@ -1433,16 +1433,6 @@ module Gitlab
         output
       end
 
-      def can_be_merged?(source_sha, target_branch)
-        gitaly_migrate(:can_be_merged) do |is_enabled|
-          if is_enabled
-            gitaly_can_be_merged?(source_sha, find_branch(target_branch).target)
-          else
-            rugged_can_be_merged?(source_sha, target_branch)
-          end
-        end
-      end
-
       def last_commit_for_path(sha, path)
         gitaly_migrate(:last_commit_for_path) do |is_enabled|
           if is_enabled
@@ -2404,14 +2394,6 @@ module Gitlab
           .map { |c| commit(c) }
       end
 
-      def gitaly_can_be_merged?(their_commit, our_commit)
-        !gitaly_conflicts_client(our_commit, their_commit).conflicts?
-      end
-
-      def rugged_can_be_merged?(their_commit, our_commit)
-        !rugged.merge_commits(our_commit, their_commit).conflicts?
-      end
-
       def last_commit_for_path_by_gitaly(sha, path)
         gitaly_commit_client.last_commit_for_path(sha, path)
       end