safe delete: allow multiple first level nodes (IDEA-135665)

java/java-impl/src/com/intellij/refactoring/safeDelete/JavaSafeDeleteProcessor.java

@@ -318,7 +318,7 @@ public class JavaSafeDeleteProcessor extends SafeDeleteProcessorDelegateBase {
       }
     }
 
-    if (delegatingParams.size() == 1) {
+    if (!delegatingParams.isEmpty()) {
       final SafeDeleteParameterCallHierarchyUsageInfo parameterHierarchyUsageInfo = delegatingParams.get(0);
       if (ApplicationManager.getApplication().isUnitTestMode()) {
         result.addAll(delegatingParams);

java/java-impl/src/com/intellij/refactoring/safeDelete/usageInfo/SafeDeleteParameterCallHierarchyUsageInfo.java

@@ -49,4 +49,26 @@ public class SafeDeleteParameterCallHierarchyUsageInfo extends SafeDeleteUsageIn
   public PsiMethod getCallerMethod() {
     return myCallerMethod;
   }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    if (!super.equals(o)) return false;
+
+    SafeDeleteParameterCallHierarchyUsageInfo info = (SafeDeleteParameterCallHierarchyUsageInfo)o;
+
+    if (!myCalledMethod.equals(info.myCalledMethod)) return false;
+    if (!myCallerMethod.equals(info.myCallerMethod)) return false;
+
+    return true;
+  }
+
+  @Override
+  public int hashCode() {
+    int result = super.hashCode();
+    result = 31 * result + myCalledMethod.hashCode();
+    result = 31 * result + myCallerMethod.hashCode();
+    return result;
+  }
 }

java/java-tests/testData/refactoring/safeDelete/DeepDeleteParameterSimple.java

@@ -4,5 +4,9 @@ class Test {
         bar(i);
     }
 
+    void baz(int i) {
+        bar(i);
+    }
+
     void bar(int <caret>i){}
 }

java/java-tests/testData/refactoring/safeDelete/DeepDeleteParameterSimple_after.java

@@ -4,5 +4,9 @@ class Test {
         bar();
     }
 
+    void baz() {
+        bar();
+    }
+
     void bar(){}
 }