Change target branch for pull request (#6488)

* Adds functionality to change target branch of created pull requests

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Use const instead of var in JavaScript additions

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Check if branches are equal and if PR already exists before changing target branch

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Make sure to check all commits

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Print error messages for user as error flash message

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Disallow changing target branch of closed or merged pull requests

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Resolve conflicts after merge of upstream/master

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Change order of branch select fields

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Removes duplicate check

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Use ctx.Tr for translations

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Recompile JS

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Use correct translation namespace

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Remove redundant if condition

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Moves most change branch logic into pull service

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Completes comment

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Add Ref to ChangesPayload for logging changed target branches
instead of creating a new struct

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Revert changes to go.mod

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Directly use createComment method

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Return 404 if pull request is not found. Move written check up

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Remove variable declaration

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Return client errors on change pull request target errors

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Return error in commit.HasPreviousCommit

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Adds blank line

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Test patch before persisting new target branch

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Update patch before testing (not working)

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Removes patch calls when changeing pull request target

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Removes unneeded check for base name

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Moves ChangeTargetBranch completely to pull service. Update patch status.

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Set webhook mode after errors were validated

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Update PR in one transaction

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Move logic for check if head is equal with branch to pull model

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Adds missing comment and simplify return

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

* Adjust CreateComment method call

Signed-off-by: Mario Lubenka <mario.lubenka@googlemail.com>

templates/repo/issue/view_content/comments.tmpl

@@ -6,7 +6,7 @@
 	 5 = COMMENT_REF, 6 = PULL_REF, 7 = COMMENT_LABEL, 12 = START_TRACKING,
 	 13 = STOP_TRACKING, 14 = ADD_TIME_MANUAL, 16 = ADDED_DEADLINE, 17 = MODIFIED_DEADLINE,
 	 18 = REMOVED_DEADLINE, 19 = ADD_DEPENDENCY, 20 = REMOVE_DEPENDENCY, 21 = CODE,
-	 22 = REVIEW, 23 = ISSUE_LOCKED, 24 = ISSUE_UNLOCKED -->
+	 22 = REVIEW, 23 = ISSUE_LOCKED, 24 = ISSUE_UNLOCKED, 25 = TARGET_BRANCH_CHANGED -->
 	{{if eq .Type 0}}
 		<div class="comment" id="{{.HashTag}}">
 		{{if .OriginalAuthor }}
@@ -411,5 +411,15 @@
 					{{$.i18n.Tr "repo.issues.unlock_comment" $createdStr | Safe}}
 				</span>
 		</div>
+	{{else if eq .Type 25}}
+		<div class="event">
+			<span class="octicon octicon-primitive-dot"></span>
+			<a class="ui avatar image" href="{{.Poster.HomeLink}}">
+				<img src="{{.Poster.RelAvatarLink}}">
+			</a>
+			<span class="text grey"><a href="{{.Poster.HomeLink}}">{{.Poster.Name}}</a>
+			{{$.i18n.Tr "repo.pulls.change_target_branch_at" (.OldRef|Escape) (.NewRef|Escape) $createdStr | Safe}}
+			</span>
+		</div>
 	{{end}}
 {{end}}