Fix ITRichfileUploadTest random failure

Error Message

Unable to locate element: {"method":"id","selector":"document_files_edit:upload:file"}
Command duration or timeout: 881 milliseconds
For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
Build info: version: '2.39.0', revision: '14fa800511cc5d66d426e08b0b2ab926c7ed7398', time: '2013-12-16 13:18:38'
System info: host: 'tweedledum', ip: '10.182.198.132', os.name: 'Windows Server 2008 R2', os.arch: 'amd64', os.version: '6.1', java.version: '1.7.0_17'
Session ID: 22b056f0-ca8d-45f5-80db-4673da98707c
Driver info: org.openqa.selenium.firefox.FirefoxDriver
Capabilities [{platform=XP, acceptSslCerts=true, javascriptEnabled=true, cssSelectorsEnabled=true, databaseEnabled=true, browserName=firefox, handlesAlerts=true, browserConnectionEnabled=true, webStorageEnabled=true, nativeEvents=false, rotatable=false, locationContextEnabled=true, applicationCacheEnabled=true, takesScreenshot=true, version=26.0}]
Stacktrace

org.openqa.selenium.NoSuchElementException: Unable to locate element: {"method":"id","selector":"document_files_edit:upload:file"}
Command duration or timeout: 881 milliseconds
For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
Build info: version: '2.39.0', revision: '14fa800511cc5d66d426e08b0b2ab926c7ed7398', time: '2013-12-16 13:18:38'
System info: host: 'tweedledum', ip: '10.182.198.132', os.name: 'Windows Server 2008 R2', os.arch: 'amd64', os.version: '6.1', java.version: '1.7.0_17'
Session ID: 22b056f0-ca8d-45f5-80db-4673da98707c
Driver info: org.openqa.selenium.firefox.FirefoxDriver
Capabilities [{platform=XP, acceptSslCerts=true, javascriptEnabled=true, cssSelectorsEnabled=true, databaseEnabled=true, browserName=firefox, handlesAlerts=true, browserConnectionEnabled=true, webStorageEnabled=true, nativeEvents=false, rotatable=false, locationContextEnabled=true, applicationCacheEnabled=true, takesScreenshot=true, version=26.0}]
	at sun.reflect.GeneratedConstructorAccessor13.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
	at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:193)
	at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:145)
	at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:554)
	at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:307)
	at org.openqa.selenium.remote.RemoteWebDriver.findElementById(RemoteWebDriver.java:348)
	at org.openqa.selenium.By$ById.findElement(By.java:220)
	at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:299)
	at org.nuxeo.functionaltests.ITRichfileUploadTest.testRichFileUpload(ITRichfileUploadTest.java:81)
Caused by: org.openqa.selenium.remote.ErrorHandler$UnknownServerException: Unable to locate element: {"method":"id","selector":"document_files_edit:upload:file"}
Build info: version: '2.39.0', revision: '14fa800511cc5d66d426e08b0b2ab926c7ed7398', time: '2013-12-16 13:18:38'
System info: host: 'tweedledum', ip: '10.182.198.132', os.name: 'Windows Server 2008 R2', os.arch: 'amd64', os.version: '6.1', java.version: '1.7.0_17'
Driver info: driver.version: unknown
	at <anonymous class&gt;.FirefoxDriver.prototype.findElementInternal_(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/driver_component.js:8860)
	at <anonymous class&gt;.FirefoxDriver.prototype.findElement(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/driver_component.js:8869)
	at <anonymous class&gt;.DelayedCommand.prototype.executeInternal_/h(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/command_processor.js:10831)
	at <anonymous class&gt;.DelayedCommand.prototype.executeInternal_(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/command_processor.js:10836)
	at <anonymous class&gt;.DelayedCommand.prototype.execute/<(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/command_processor.js:10778)
Standard Output

18:22:40,306 ERROR [AbstractTest] Test 'org.nuxeo.functionaltests.ITRichfileUploadTest#testRichFileUpload' failed
org.openqa.selenium.NoSuchElementException: Unable to locate element: {"method":"id","selector":"document_files_edit:upload:file"}
Command duration or timeout: 881 milliseconds
For documentation on this error, please visit: http://seleniumhq.org/exceptions/no_such_element.html
Build info: version: '2.39.0', revision: '14fa800511cc5d66d426e08b0b2ab926c7ed7398', time: '2013-12-16 13:18:38'
System info: host: 'tweedledum', ip: '10.182.198.132', os.name: 'Windows Server 2008 R2', os.arch: 'amd64', os.version: '6.1', java.version: '1.7.0_17'
Session ID: 22b056f0-ca8d-45f5-80db-4673da98707c
Driver info: org.openqa.selenium.firefox.FirefoxDriver
Capabilities [{platform=XP, acceptSslCerts=true, javascriptEnabled=true, cssSelectorsEnabled=true, databaseEnabled=true, browserName=firefox, handlesAlerts=true, browserConnectionEnabled=true, webStorageEnabled=true, nativeEvents=false, rotatable=false, locationContextEnabled=true, applicationCacheEnabled=true, takesScreenshot=true, version=26.0}]
	at sun.reflect.GeneratedConstructorAccessor13.newInstance(Unknown Source)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
	at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:193)
	at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:145)
	at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:554)
	at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:307)
	at org.openqa.selenium.remote.RemoteWebDriver.findElementById(RemoteWebDriver.java:348)
	at org.openqa.selenium.By$ById.findElement(By.java:220)
	at org.openqa.selenium.remote.RemoteWebDriver.findElement(RemoteWebDriver.java:299)
	at org.nuxeo.functionaltests.ITRichfileUploadTest.testRichFileUpload(ITRichfileUploadTest.java:81)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:601)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
	at org.nuxeo.functionaltests.LogTestWatchman$1.evaluate(LogTestWatchman.java:96)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:76)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
	at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:28)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:31)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
	at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:264)
	at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:153)
	at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:124)
	at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:200)
	at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:153)
	at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103)
Caused by: org.openqa.selenium.remote.ErrorHandler$UnknownServerException: Unable to locate element: {"method":"id","selector":"document_files_edit:upload:file"}
Build info: version: '2.39.0', revision: '14fa800511cc5d66d426e08b0b2ab926c7ed7398', time: '2013-12-16 13:18:38'
System info: host: 'tweedledum', ip: '10.182.198.132', os.name: 'Windows Server 2008 R2', os.arch: 'amd64', os.version: '6.1', java.version: '1.7.0_17'
Driver info: driver.version: unknown
	at <anonymous class&gt;.FirefoxDriver.prototype.findElementInternal_(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/driver_component.js:8860)
	at <anonymous class&gt;.FirefoxDriver.prototype.findElement(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/driver_component.js:8869)
	at <anonymous class&gt;.DelayedCommand.prototype.executeInternal_/h(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/command_processor.js:10831)
	at <anonymous class&gt;.DelayedCommand.prototype.executeInternal_(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/command_processor.js:10836)
	at <anonymous class&gt;.DelayedCommand.prototype.execute/<(file:///C:/Users/nuxeo/AppData/Local/Temp/anonymous3081698045696720063webdriver-profile/extensions/fxdriver@googlecode.com/components/command_processor.js:10778)