Move fileapi into its own component

webkit/fileapi/webfilewriter_base.h

Index: webkit/fileapi/webfilewriter_base.h
diff --git a/webkit/fileapi/webfilewriter_base.h b/webkit/fileapi/webfilewriter_base.h
index ec02a1c6c0ea0ef519b02f6c9c3705ce582d8542..735323aefcb396a62a04276628fce7088093580f 100644
--- a/webkit/fileapi/webfilewriter_base.h
+++ b/webkit/fileapi/webfilewriter_base.h
@@ -8,6 +8,7 @@
 #include "base/platform_file.h"
 #include "googleurl/src/gurl.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebFileWriter.h"
+#include "webkit/fileapi/fileapi_export.h"
 
 namespace WebKit {
 class WebFileWriterClient;
@@ -16,7 +17,8 @@ class WebURL;
 
 namespace fileapi {
 
-class WebFileWriterBase : public WebKit::WebFileWriter {
+class FILEAPI_EXPORT WebFileWriterBase
+    : public NON_EXPORTED_BASE(WebKit::WebFileWriter) {
  public:
   WebFileWriterBase(
       const GURL& path, WebKit::WebFileWriterClient* client);