call single unichar variant of api

More clear, and simplifies future skia api changes.

Change-Id: I2f8172e4292bdf63c1e06843ee080ace3baa29e7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1566113Reviewed-by: Ben Wagner <bungeman@google.com>
Reviewed-by: Pavel Feldman <pfeldman@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
Cr-Commit-Position: refs/heads/master@{#650481}

third_party/blink/renderer/platform/fonts/simple_font_data.cc

@@ -191,11 +191,9 @@ const SimpleFontData* SimpleFontData::FontDataForCharacter(UChar32) const {
 }
 
 Glyph SimpleFontData::GlyphForCharacter(UChar32 codepoint) const {
-  uint16_t glyph;
   SkTypeface* typeface = PlatformData().Typeface();
   CHECK(typeface);
-  typeface->charsToGlyphs(&codepoint, SkTypeface::kUTF32_Encoding, &glyph, 1);
-  return glyph;
+  return typeface->unicharToGlyph(codepoint);
 }
 
 bool SimpleFontData::IsSegmented() const {