Fix win/clang part 2.

After moving EmbeddedUnicodeFromCharcode the
IsValidEmbeddedCharcodeFromUnicodeCharset method is no longer used on windows.

TBR=weili@chromium.org

Review URL: https://codereview.chromium.org/1827823002 .
diff --git a/core/fpdfapi/fpdf_font/fpdf_font_cid.cpp b/core/fpdfapi/fpdf_font/fpdf_font_cid.cpp
index 98051cb..b952cda 100644
--- a/core/fpdfapi/fpdf_font/fpdf_font_cid.cpp
+++ b/core/fpdfapi/fpdf_font/fpdf_font_cid.cpp
@@ -284,6 +284,8 @@
   return 1;
 }
 
+#if _FXM_PLATFORM_ != _FXM_PLATFORM_WINDOWS_
+
 bool IsValidEmbeddedCharcodeFromUnicodeCharset(CIDSet charset) {
   switch (charset) {
     case CIDSET_GB1:
@@ -297,8 +299,6 @@
   }
 }
 
-#if _FXM_PLATFORM_ != _FXM_PLATFORM_WINDOWS_
-
 FX_DWORD EmbeddedCharcodeFromUnicode(const FXCMAP_CMap* pEmbedMap,
                                      CIDSet charset,
                                      FX_WCHAR unicode) {