[Media Gallery] Added code to support mtp device media file system on Windows.

webkit/fileapi/file_system_file_util.h

Index: webkit/fileapi/file_system_file_util.h
diff --git a/webkit/fileapi/file_system_file_util.h b/webkit/fileapi/file_system_file_util.h
index 6593c9743210f6d4d0d1ec40df5efb34b42f3c0e..a1e4e892bcb2e923502bf0c61be5a213ce1417f3 100644
--- a/webkit/fileapi/file_system_file_util.h
+++ b/webkit/fileapi/file_system_file_util.h
@@ -31,7 +31,7 @@ class FileSystemOperationContext;
 class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
  public:
   // It will be implemented by each subclass such as FileSystemFileEnumerator.
-  class AbstractFileEnumerator {
+  class WEBKIT_STORAGE_EXPORT AbstractFileEnumerator {
    public:
     virtual ~AbstractFileEnumerator() {}
 
@@ -57,7 +57,8 @@ class WEBKIT_STORAGE_EXPORT FileSystemFileUtil {
     kSnapshotFileTemporary,
   };
 
-  class EmptyFileEnumerator : public AbstractFileEnumerator {
+  class WEBKIT_STORAGE_EXPORT EmptyFileEnumerator
+      : public AbstractFileEnumerator {
     virtual FilePath Next() OVERRIDE;
     virtual int64 Size() OVERRIDE;
     virtual base::Time LastModifiedTime() OVERRIDE;