Early out of expensive script-size logging in Link when LogLevel > TRACE.

Review by: spoon (desk)

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@5339 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/dev/core/src/com/google/gwt/dev/Link.java b/dev/core/src/com/google/gwt/dev/Link.java
index a1fec18..ec82b83 100644
--- a/dev/core/src/com/google/gwt/dev/Link.java
+++ b/dev/core/src/com/google/gwt/dev/Link.java
@@ -253,6 +253,10 @@
    */
   private static void logScriptSize(TreeLogger logger, int permId,
       StandardCompilationResult compilation) {
+    if (!logger.isLoggable(TreeLogger.TRACE)) {
+      return;
+    }
+
     String[] javaScript = compilation.getJavaScript();
 
     int[] jsLengths = new int[javaScript.length];