to avoid API breakage, restore PathUIUtils class as deprecated

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/LibrarySourceRootDetectorUtil.java

@@ -37,7 +37,7 @@ import java.util.List;
 public class LibrarySourceRootDetectorUtil {
   public static ExtensionPointName<RootDetector> JAVA_SOURCE_ROOT_DETECTOR = ExtensionPointName.create("com.intellij.library.javaSourceRootDetector");
 
-  private LibrarySourceRootDetectorUtil() {
+  protected LibrarySourceRootDetectorUtil() {
   }
 
   /**

java/idea-ui/src/com/intellij/openapi/roots/ui/configuration/PathUIUtils.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2000-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.intellij.openapi.roots.ui.configuration;
+
+import com.intellij.openapi.roots.libraries.ui.RootDetector;
+
+/**
+ * @deprecated please use {@link LibrarySourceRootDetectorUtil} directly
+ */
+public class PathUIUtils extends LibrarySourceRootDetectorUtil {
+  public static final RootDetector JAVA_SOURCE_ROOT_DETECTOR = new LibraryJavaSourceRootDetector();
+
+}