introduce JBColor.isBright() for better use with lambdas

platform/util/src/com/intellij/ui/JBColor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2014 JetBrains s.r.o.
+ * 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.
@@ -58,6 +58,10 @@ public class JBColor extends Color {
     DARK = dark;
   }
 
+  public static boolean isBright() {
+    return !DARK;
+  }
+
   Color getDarkVariant() {
     return darkColor;
   }