node.cloneNode() should clone the value of file upload elements

Source/core/html/HTMLInputElement.cpp

Index: Source/core/html/HTMLInputElement.cpp
diff --git a/Source/core/html/HTMLInputElement.cpp b/Source/core/html/HTMLInputElement.cpp
index 7952c58f83be743b8803e9610ed433ab59f45558..913734697ee9f8ec6aa45e57fd066bbf4af68391 100644
--- a/Source/core/html/HTMLInputElement.cpp
+++ b/Source/core/html/HTMLInputElement.cpp
@@ -909,6 +909,16 @@ void HTMLInputElement::copyNonAttributePropertiesFromElement(const Element& sour
     setChecked(sourceElement.m_isChecked);
     m_reflectsCheckedAttribute = sourceElement.m_reflectsCheckedAttribute;
     m_isIndeterminate = sourceElement.m_isIndeterminate;
+    if (isFileUpload()) {
+        RefPtrWillBeRawPtr<FileList> fileList(FileList::create());
+        FileList* sourceFileList = sourceElement.files();
+        unsigned size = sourceFileList->length();
+        for (unsigned i = 0; i < size; ++i) {
+            File* file = sourceFileList->item(i);
+            fileList->append(File::createWithRelativePath(file->path(), file->webkitRelativePath()));
+        }
+        setFiles(fileList.release());
+    }
 
     HTMLTextFormControlElement::copyNonAttributePropertiesFromElement(source);
 
@@ -1319,7 +1329,7 @@ KURL HTMLInputElement::src() const
     return document().completeURL(fastGetAttribute(srcAttr));
 }
 
-FileList* HTMLInputElement::files()
+FileList* HTMLInputElement::files() const
 {
     return m_inputType->files();
 }