Do not calculate size for missing characters.

Since we are rendering in only the chosen font, if the character in
question does not exist simply report its size as zero.

```
Fixes fvwmorg#622, fixes fvwmorg#680.
```

libs/Fft.c

@@ -286,7 +286,6 @@ static void MatchFont(Display *dpy,
 		      void (*render_char)(void *, XftCharFontSpec *),
 		      void *user_data)
 {
-	FcPattern *template = NULL;
 	int codelen = 0, off = 0;
 
 	for (off = 0; off < len; off += codelen) {
@@ -303,56 +302,17 @@ static void MatchFont(Display *dpy,
 			continue;
 		}
 
-		if (!XftCharExists(dpy, font, sp.ucs4)) {
-			/* Fallback */
-			if (!template) {
-				int slant = 0, weight = 0;
-				double font_size = 0.0;
-				FcPatternGetDouble(font->pattern, FC_SIZE, 0, &font_size);
-				FcPatternGetInteger(font->pattern, FC_WEIGHT, 0, &weight);
-				FcPatternGetInteger(font->pattern, FC_SLANT, 0, &slant);
-				template = FcPatternBuild(
-				    NULL,
-				    FC_SIZE, FcTypeDouble, font_size,
-				    FC_WEIGHT, FcTypeInteger, weight,
-				    FC_SLANT, FcTypeInteger, slant,
-				    NULL);
-			} else {
-				FcPatternDel(template, FC_CHARSET);
-			}
-
-			FcCharSet *fallback_charset = FcCharSetCreate();
-			FcCharSetAddChar(fallback_charset, sp.ucs4);
-			FcPatternAddCharSet(template, FC_CHARSET, fallback_charset);
+		if (XftCharExists(dpy, font, sp.ucs4)) {
+			XGlyphInfo info;
+			XftTextExtents32(dpy, sp.font, &sp.ucs4, 1, &info);
+			*xoff += info.xOff;
+			*yoff += info.yOff;
 
-			/* Lookup from the cache first! */
-			FcResult result = FcResultMatch;
-			FcPattern *font_pattern = MatchCacheFont(sp.ucs4, template, &result);
-			if (!font_pattern) {
-				font_pattern = XftFontMatch(dpy, XDefaultScreen(dpy), template, &result);
-				if (font_pattern) AddCacheFont(sp.ucs4, template, font_pattern);
+			if (render_char) {
+				render_char(user_data, &sp);
 			}
-			FcCharSetDestroy(fallback_charset);
-
-			if (result == FcResultMatch) {
-				XftFont *fallback_font = XftFontOpenPattern(dpy, font_pattern);
-				if (fallback_font) sp.font = fallback_font;
-				else FcPatternDestroy(font_pattern);
-			}
-		}
-		XGlyphInfo info;
-		XftTextExtents32(dpy, sp.font, &sp.ucs4, 1, &info);
-		*xoff += info.xOff;
-		*yoff += info.yOff;
-
-		if (render_char) {
-			render_char(user_data, &sp);
-		} else if (sp.font != font) {
-			XftFontClose(dpy, sp.font);
 		}
 	}
-	if (template)
-		FcPatternDestroy(template);
 }
 
 #define NR_CHARFONTSPEC 31