title: Unable to Create War in Grails With Asset Pipeline plugin
body: <p>I am trying to include Asset Pipeline plugin to manage my static resource, Everything worked smoothly until I tried deploying war from my project. I am getting the following error. I am using Grails-2.2.4 and asset-pipeline:1.9.7</p>
  
  <pre><code>| Error Error executing script RunWar: java.lang.RuntimeException: Property already 
  
  exists (NOTE: Stack trace has been filtered. Use --verbose to see entire trace.)
  java.lang.RuntimeException: Property already exists
      at org.mozilla.javascript.ScriptableObject.defineProperty(Unknown Source)
      at org.mozilla.javascript.LazilyLoadedCtor.&lt;init&gt;(Unknown Source)
      at org.mozilla.javascript.ScriptRuntime.initStandardObjects(Unknown Source)
      at org.mozilla.javascript.Context.initStandardObjects(Unknown Source)
      at org.mozilla.javascript.Context.initStandardObjects(Unknown Source)
      at org.mozilla.javascript.Context$initStandardObjects.call(Unknown Source)
      at asset.pipeline.processors.UglifyJsProcessor.&lt;init&gt;(UglifyJsProcessor.groovy:54)
      at asset.pipeline.AssetCompiler.compile(AssetCompiler.groovy:39)
      at asset.pipeline.AssetCompiler$compile.call(Unknown Source)
      at _AssetCompile_groovy$_run_closure2.doCall(_AssetCompile_groovy:49)
      at org.codehaus.gant.GantMetaClass.invokeMethod(GantMetaClass.java:133)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16_closure18.doCall(GantBinding.groovy:185)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16_closure18.doCall(GantBinding.groovy)
      at org.codehaus.gant.GantBinding.withTargetEvent(GantBinding.groovy:90)
      at org.codehaus.gant.GantBinding.this$4$withTargetEvent(GantBinding.groovy)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16.doCall(GantBinding.groovy:185)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16.doCall(GantBinding.groovy)
      at _Events$_run_closure1.doCall(_Events.groovy:5)
      at _GrailsWar_groovy$_run_closure2.doCall(_GrailsWar_groovy:43)
      at org.codehaus.gant.GantMetaClass.invokeMethod(GantMetaClass.java:133)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16_closure18.doCall(GantBinding.groovy:185)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16_closure18.doCall(GantBinding.groovy)
      at org.codehaus.gant.GantBinding.withTargetEvent(GantBinding.groovy:90)
      at org.codehaus.gant.GantBinding.this$4$withTargetEvent(GantBinding.groovy)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16.doCall(GantBinding.groovy:185)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16.doCall(GantBinding.groovy)
      at org.codehaus.gant.GantMetaClass.invokeMethod(GantMetaClass.java:133)
      at RunWar$_run_closure1.doCall(RunWar.groovy:42)
      at org.codehaus.gant.GantMetaClass.invokeMethod(GantMetaClass.java:133)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16_closure18.doCall(GantBinding.groovy:185)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16_closure18.doCall(GantBinding.groovy)
      at org.codehaus.gant.GantBinding.withTargetEvent(GantBinding.groovy:90)
      at org.codehaus.gant.GantBinding.this$4$withTargetEvent(GantBinding.groovy)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16.doCall(GantBinding.groovy:185)
      at org.codehaus.gant.GantBinding$_initializeGantBinding_closure5_closure16.doCall(GantBinding.groovy)
      at gant.Gant$_dispatch_closure5.doCall(Gant.groovy:381)
      at gant.Gant$_dispatch_closure7.doCall(Gant.groovy:415)
      at gant.Gant$_dispatch_closure7.doCall(Gant.groovy)
      at gant.Gant.withBuildListeners(Gant.groovy:427)
      at gant.Gant.this$2$withBuildListeners(Gant.groovy)
      at gant.Gant$this$2$withBuildListeners.callCurrent(Unknown Source)
      at gant.Gant.dispatch(Gant.groovy:415)
      at gant.Gant.this$2$dispatch(Gant.groovy)
      at gant.Gant.invokeMethod(Gant.groovy)
      at gant.Gant.executeTargets(Gant.groovy:591)
      at gant.Gant.executeTargets(Gant.groovy:590)
  | Error Error executing script RunWar: java.lang.RuntimeException: Property already exists
  </code></pre>