Fix some FX_BOOL / int noise in fxcrt.

core/fxcrt/fxcrt_windows.cpp

Index: core/fxcrt/fxcrt_windows.cpp
diff --git a/core/fxcrt/fxcrt_windows.cpp b/core/fxcrt/fxcrt_windows.cpp
index ec16373f02dafa3b3d57c97dd13d94de010d2e8a..b40f06ecbae890aae5841991d775d745552e1609 100644
--- a/core/fxcrt/fxcrt_windows.cpp
+++ b/core/fxcrt/fxcrt_windows.cpp
@@ -160,12 +160,12 @@ FX_BOOL CFXCRT_FileAccess_Win64::Flush() {
   if (!m_hFile) {
     return FALSE;
   }
-  return ::FlushFileBuffers(m_hFile);
+  return !!::FlushFileBuffers(m_hFile);
 }
 FX_BOOL CFXCRT_FileAccess_Win64::Truncate(FX_FILESIZE szFile) {
   if (SetPosition(szFile) == (FX_FILESIZE)-1) {
     return FALSE;
   }
-  return ::SetEndOfFile(m_hFile);
+  return !!::SetEndOfFile(m_hFile);
 }
 #endif