Branches not at ref commit ID should not be listed as Merged (#9614)

Once a branch has been merged if the commit ID no longer equals that of
the pulls ref commit id don't offer to delete the branch on the pull screen
and don't list it as merged on branches.

Fix #9201

When looking at the pull page we should also get the commits from the refs/pulls/x/head

Fix #9158

templates/repo/branch/list.tmpl

@@ -84,6 +84,12 @@
 												<button id="new-pull-request" class="ui compact basic button">{{$.i18n.Tr "repo.pulls.compare_changes"}}</button>
 											</a>
 											{{end}}
+										{{else if and .LatestPullRequest.HasMerged .MergeMovedOn}}
+											{{if and (not .IsDeleted) $.AllowsPulls (gt .CommitsAhead 0)}}
+											<a href="{{$.RepoLink}}/compare/{{$.DefaultBranch | EscapePound}}...{{if ne $.Repository.Owner.Name $.Owner.Name}}{{$.Owner.Name}}:{{end}}{{.Name | EscapePound}}">
+												<button id="new-pull-request" class="ui compact basic button">{{$.i18n.Tr "repo.pulls.compare_changes"}}</button>
+											</a>
+											{{end}}
 										{{else}}
 											<a href="{{$.RepoLink}}/pulls/{{.LatestPullRequest.Issue.Index}}">#{{.LatestPullRequest.Issue.Index}}</a>
 											{{if .LatestPullRequest.HasMerged}}

templates/repo/issue/view_content/pull.tmpl

@@ -72,7 +72,7 @@
 						{{$.i18n.Tr "repo.pulls.reopen_to_merge"}}
 					{{end}}
 				</div>
-				{{if .IsPullBranchDeletable}}
+				{{if and .IsPullBranchDeletable ( not .IsPullRequestBroken )}}
 					<div class="ui divider"></div>
 					<div>
 						<a class="delete-button ui red button" href="" data-url="{{.DeleteBranchLink}}">{{$.i18n.Tr "repo.branch.delete" .HeadTarget}}</a>
@@ -105,7 +105,7 @@
 				<div class="item text red">
 					<span class="octicon octicon-x"></span>
 				{{$.i18n.Tr "repo.pulls.blocked_by_rejection"}}
-				</div>			
+				</div>
 			{{else if .Issue.PullRequest.IsChecking}}
 				<div class="item text yellow">
 					<span class="octicon octicon-sync"></span>