Merge branch 'issues-show-performance' into 'master'

Improve performance of viewing individual issues

This MR does two things:

1. `Issue#related_branches` no longer performs Git operations that aren't needed
2. The output of `Repository#exists?` is now cached and flushed properly

Combined these two changes should further cut down the amount of Git operations performed when viewing individual issues (and possibly other pages).

See merge request !3296

1 files changed, 3 insertions, 3 deletions

diff --git a/app/models/issue.rb b/app/models/issue.rb
index 35e08fa915b..ddb51ad5775 100644
--- a/app/models/issue.rb
+++ b/app/models/issue.rb
@@ -108,9 +108,9 @@ class Issue < ActiveRecord::Base
   end
 
   def related_branches
-    return [] if self.project.empty_repo?
-    
-    self.project.repository.branch_names.select { |branch| branch.end_with?("-#{iid}") }
+    project.repository.branch_names.select do |branch|
+      branch.end_with?("-#{iid}")
+    end
   end
 
   # Reset issue events cache