Fix rendering with built-in CID fonts

The root cause is that FXFONT_SUBST_EXACT is wrongly
set even no any subset font was found. It causes
m_bCIDIsGID to be wrongly set as TRUE in CPDF_CIDFont::_Load().

BUG=534945
R=thestig@chromium.org, tsepez@chromium.org

Review URL: https://codereview.chromium.org/1502083002 .
diff --git a/core/src/fxge/ge/fx_ge_fontmap.cpp b/core/src/fxge/ge/fx_ge_fontmap.cpp
index 52605a0..6781369 100644
--- a/core/src/fxge/ge/fx_ge_fontmap.cpp
+++ b/core/src/fxge/ge/fx_ge_fontmap.cpp
@@ -1052,7 +1052,6 @@
             : (nStyle & FX_FONT_STYLE_Bold ? FXFONT_FW_BOLD : FXFONT_FW_NORMAL);
   }
   if (!match.IsEmpty() || iBaseFont < 12) {
-    pSubstFont->m_SubstFlags |= FXFONT_SUBST_EXACT;
     if (!match.IsEmpty()) {
       family = match;
     }