Remove two more unused variables that compilers now complain about.

core/src/fxge/win32/fx_win32_gdipext.cpp

Index: core/src/fxge/win32/fx_win32_gdipext.cpp
diff --git a/core/src/fxge/win32/fx_win32_gdipext.cpp b/core/src/fxge/win32/fx_win32_gdipext.cpp
index 2022a5f9575f62342ce4a137edbf30a7ed0c8b88..42f8a4a29f4215c1a7d493ae60de8bba7c8e978f 100644
--- a/core/src/fxge/win32/fx_win32_gdipext.cpp
+++ b/core/src/fxge/win32/fx_win32_gdipext.cpp
@@ -482,8 +482,6 @@ static CFX_DIBitmap* _StretchMonoToGray(int dest_width,
   LPBYTE dest_buf = pStretched->GetBuffer();
   int src_width = pSource->GetWidth();
   int src_height = pSource->GetHeight();
-  int src_count = src_width * src_height;
-  int dest_count = dest_width * dest_height;
   int y_unit = src_height / dest_height;
   int x_unit = src_width / dest_width;
   int area_unit = y_unit * x_unit;