Remove the unused IFX_StreamRead::SetRange() mechanism.

core/include/fxcrt/fx_stream.h

Index: core/include/fxcrt/fx_stream.h
diff --git a/core/include/fxcrt/fx_stream.h b/core/include/fxcrt/fx_stream.h
index 73ec7e05b206bec00876e3a1f4a0b7fdb44af708..7856dcbb1205ae00574094a483f0e17c7868c926 100644
--- a/core/include/fxcrt/fx_stream.h
+++ b/core/include/fxcrt/fx_stream.h
@@ -100,12 +100,6 @@ class IFX_FileRead : IFX_StreamRead {
 
   virtual FX_FILESIZE GetPosition() { return 0; }
 
-  virtual FX_BOOL SetRange(FX_FILESIZE offset, FX_FILESIZE size) {
-    return FALSE;
-  }
-
-  virtual void ClearRange() {}
-
   virtual FX_BOOL ReadBlock(void* buffer, FX_FILESIZE offset, size_t size) = 0;
 
   virtual size_t ReadBlock(void* buffer, size_t size) { return 0; }