[java] remove unused field together with the javadoc (IDEA-293707)

GitOrigin-RevId: eefeda71df06e537d5a2d07119bb8724a70f5def

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/quickfix/RemoveUnusedVariableUtil.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+// Copyright 2000-2022 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.codeInsight.daemon.impl.quickfix;
 
 import com.intellij.psi.*;
@@ -220,6 +220,9 @@ public final class RemoveUnusedVariableUtil {
   private static void deleteVariable(PsiVariable variable) {
     CommentTracker tracker = new CommentTracker();
     tracker.markUnchanged(variable.getInitializer()); // assume that initializer is used (e.g. inlined)
+    if (variable instanceof PsiJavaDocumentedElement) {
+      tracker.markUnchanged(((PsiJavaDocumentedElement)variable).getDocComment());
+    }
     tracker.deleteAndRestoreComments(variable);
   }
 

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/removeUnusedVariable/afterField3.java

@@ -0,0 +1,6 @@
+// "Remove field 'k'" "true"
+import java.io.*;
+
+class a {
+}
+

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/removeUnusedVariable/beforeField3.java

@@ -0,0 +1,10 @@
+// "Remove field 'k'" "true"
+import java.io.*;
+
+class a {
+  /**
+   * Demo
+   */
+  private int <caret>k;
+}
+