patch 9.0.1577: MS-Windows: context menu translations may be wrong

Problem:    MS-Windows: context menu translations may be wrong.
Solution:   Set the encoding before using gettext(). (Ken Takata,
            closes #12441, closes #12431)
diff --git a/src/GvimExt/gvimext.h b/src/GvimExt/gvimext.h
index b85f32e..e7bcfb8 100644
--- a/src/GvimExt/gvimext.h
+++ b/src/GvimExt/gvimext.h
@@ -81,21 +81,20 @@
 class CShellExtClassFactory : public IClassFactory
 {
 protected:
-	ULONG	m_cRef;
+    ULONG	m_cRef;
 
 public:
-	CShellExtClassFactory();
-	~CShellExtClassFactory();
+    CShellExtClassFactory();
+    ~CShellExtClassFactory();
 
-	//IUnknown members
-	STDMETHODIMP			QueryInterface(REFIID, LPVOID FAR *);
-	STDMETHODIMP_(ULONG)	AddRef();
-	STDMETHODIMP_(ULONG)	Release();
+    //IUnknown members
+    STDMETHODIMP		QueryInterface(REFIID, LPVOID FAR *);
+    STDMETHODIMP_(ULONG)	AddRef();
+    STDMETHODIMP_(ULONG)	Release();
 
-	//IClassFactory members
-	STDMETHODIMP		CreateInstance(LPUNKNOWN, REFIID, LPVOID FAR *);
-	STDMETHODIMP		LockServer(BOOL);
-
+    //IClassFactory members
+    STDMETHODIMP		CreateInstance(LPUNKNOWN, REFIID, LPVOID FAR *);
+    STDMETHODIMP		LockServer(BOOL);
 };
 typedef CShellExtClassFactory *LPCSHELLEXTCLASSFACTORY;
 #define MAX_HWND 100