safe delete: check hierarchy excluding current method (IDEA-150176)

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

@@ -172,7 +172,7 @@ public class JavaSafeDeleteProcessor extends SafeDeleteProcessorDelegateBase {
                 return true;
               }
             });
-            if (!overriders.isEmpty()) {
+            if (overriders.size() > 1) {
               String message = RefactoringBundle.message("0.is.a.part.of.method.hierarchy.do.you.want.to.delete.multiple.type.parameters", UsageViewUtil.getLongName(owner));
               int result = ApplicationManager.getApplication().isUnitTestMode() 
                            ? Messages.YES :Messages.showYesNoCancelDialog(project, message, SafeDeleteHandler.REFACTORING_NAME, Messages.getQuestionIcon());

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

@@ -0,0 +1,3 @@
+class A {
+  public <<caret>T> void foo() {}
+}

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

@@ -0,0 +1,3 @@
+class A {
+  public void foo() {}
+}

java/java-tests/testSrc/com/intellij/refactoring/SafeDeleteTest.java

@@ -280,6 +280,10 @@ public class SafeDeleteTest extends MultiFileTestCase {
   public void testTypeParameterWithinMethodHierarchy() throws Exception {
     doSingleFileTest();
   }
+  
+  public void testTypeParameterNoMethodHierarchy() throws Exception {
+    doSingleFileTest();
+  }
 
   public void testClassWithInnerStaticImport() throws Exception {
     doTest("ClassWithInnerStaticImport");