Remove duplicated charset definitions, and move them to fx_font.h

PWL_FontMap does not need its own charset definitions. fx_edit.h does
not need to define DEFAULT_CHARSET. XFA have their own definitions.
They look different in that most are MAC or MSWin charset definitions.
So they are left untouched. public/fpdf_sysfontinfo.h duplicate ones
were left untouched due to being in public folder.

Review-Url: https://codereview.chromium.org/2347313002
diff --git a/fpdfsdk/fxedit/fxet_edit.cpp b/fpdfsdk/fxedit/fxet_edit.cpp
index 4967961..528a0ba 100644
--- a/fpdfsdk/fxedit/fxet_edit.cpp
+++ b/fpdfsdk/fxedit/fxet_edit.cpp
@@ -633,7 +633,7 @@
   if (m_pEdit) {
     m_pEdit->SelectNone();
     m_pEdit->SetCaret(m_wrSel.BeginPos);
-    m_pEdit->InsertText(m_swText, DEFAULT_CHARSET, FALSE, TRUE);
+    m_pEdit->InsertText(m_swText, FXFONT_DEFAULT_CHARSET, FALSE, TRUE);
     m_pEdit->SetSel(m_wrSel.BeginPos, m_wrSel.EndPos);
   }
 }
@@ -1271,7 +1271,7 @@
 
 void CFX_Edit::SetText(const CFX_WideString& sText) {
   Empty();
-  DoInsertText(CPVT_WordPlace(0, 0, -1), sText, DEFAULT_CHARSET);
+  DoInsertText(CPVT_WordPlace(0, 0, -1), sText, FXFONT_DEFAULT_CHARSET);
   Paint();
 }