Git: Add "Show HEAD" link in amend commit editor

Fixes: QTCREATORBUG-25004
Change-Id: Idac181c8821da41a21d86cb1760691d51158daee
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>
Reviewed-by: André Hartmann <aha_1980@gmx.de>

src/plugins/git/gitsubmiteditorwidget.cpp

@@ -65,6 +65,8 @@ GitSubmitEditorWidget::GitSubmitEditorWidget() :
             this, &GitSubmitEditorWidget::authorInformationChanged);
     connect(m_gitSubmitPanelUi.emailLineEdit, &QLineEdit::textChanged,
             this, &GitSubmitEditorWidget::authorInformationChanged);
+    connect(m_gitSubmitPanelUi.showHeadLabel, &QLabel::linkActivated,
+            this, [this] { emit showRequested("HEAD"); });
 }
 
 void GitSubmitEditorWidget::setPanelInfo(const GitSubmitEditorPanelInfo &info)
@@ -99,6 +101,8 @@ void GitSubmitEditorWidget::initialize(CommitType commitType,
     if (m_isInitialized)
         return;
     m_isInitialized = true;
+    if (commitType != AmendCommit)
+        m_gitSubmitPanelUi.showHeadLabel->hide();
     if (commitType == FixupCommit) {
         auto logChangeGroupBox = new QGroupBox(tr("Select Change"));
         auto logChangeLayout = new QVBoxLayout;

src/plugins/git/gitsubmitpanel.ui

@@ -60,6 +60,13 @@
         </property>
        </widget>
       </item>
+      <item row="2" column="0" colspan="2">
+       <widget class="QLabel" name="showHeadLabel">
+        <property name="text">
+         <string>&lt;a href=&quot;head&quot;&gt;Show HEAD&lt;/a&gt;</string>
+        </property>
+       </widget>
+      </item>
      </layout>
     </widget>
    </item>