Replace calls to deprecated CFX_{Wide,Byte}String::Empty()

core/fxcrt/fx_basic_buffer.cpp

Index: core/fxcrt/fx_basic_buffer.cpp
diff --git a/core/fxcrt/fx_basic_buffer.cpp b/core/fxcrt/fx_basic_buffer.cpp
index 7f85c95d3fa87e510b126fa92908feb02ae1ffde..1e5d0554d1ded8ecbb63f590902ca7638f67a76e 100644
--- a/core/fxcrt/fx_basic_buffer.cpp
+++ b/core/fxcrt/fx_basic_buffer.cpp
@@ -290,7 +290,7 @@ CFX_ArchiveLoader& CFX_ArchiveLoader::operator>>(CFX_ByteString& str) {
   }
   int len;
   operator>>(len);
-  str.Empty();
+  str.clear();
   if (len <= 0 || m_LoadingPos + len > m_LoadingSize) {
     return *this;
   }