More flexible logger factory access and initialization

This allows to create a logger that wraps the standard IDEA logger (for rdserver)

platform/util/src/com/intellij/openapi/diagnostic/Logger.java

@@ -1,6 +1,4 @@
-/*
- * Copyright 2000-2017 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 2000-2018 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.
 package com.intellij.openapi.diagnostic;
 
 import com.intellij.util.ArrayUtil;
@@ -52,6 +50,19 @@ public abstract class Logger {
     }
   }
 
+  public static void setFactory(Factory factory) {
+    if (isInitialized()) {
+      //noinspection UseOfSystemOutOrSystemErr
+      System.out.println("Changing log factory\n" + ExceptionUtil.getThrowableText(new Throwable()));
+    }
+
+    ourFactory = factory;
+  }
+
+  public static Factory getFactory() {
+    return ourFactory;
+  }
+
   public static boolean isInitialized() {
     return !(ourFactory instanceof DefaultFactory);
   }