Refactor Gitlab::ProjectSearchResults

Previously this class would be given a project ID which was then used to
retrieve the corresponding Project object. However, in all cases the
Project object was already known as it was used to grab the ID to pass
to ProjectSearchResults. By just passing a Project instead we remove the
need for an extra query as well as the need for some other complexity
in this class.

app/services/search/project_service.rb

@@ -7,7 +7,7 @@ module Search
     end
     def execute
-      Gitlab::ProjectSearchResults.new(project.id,
+      Gitlab::ProjectSearchResults.new(project,
                                        params[:search],
                                        params[:repository_ref])
     end

lib/gitlab/project_search_results.rb

@@ -2,8 +2,8 @@ module Gitlab
   class ProjectSearchResults < SearchResults
     attr_reader :project, :repository_ref
-    def initialize(project_id, query, repository_ref = nil)
-      @project = Project.find(project_id)
+    def initialize(project, query, repository_ref = nil)
+      @project = project
       @repository_ref = if repository_ref.present?
                           repository_ref
                         else
@@ -73,7 +73,7 @@ module Gitlab
     end
     def notes
-      Note.where(project_id: limit_project_ids).user.search(query).order('updated_at DESC')
+      project.notes.user.search(query).order('updated_at DESC')
     end
     def commits
@@ -83,9 +83,5 @@ module Gitlab
         project.repository.find_commits_by_message(query).compact
       end
     end
-
-    def limit_project_ids
-      [project.id]
-    end
   end
 end