Simplify nvpr text

- Drops device-space glyphs in favor of perf/simplicity.

- Removes residual complexities that would flip glyphs vertically for
  compatibility with nvpr glyph loading, which is no longer used.

- Drops hairline support since they required new paths for every draw
  matrix, and could only be supported under certain circumstances.

- Quits checking for color bitmap fonts in canDrawText since the
  normal color emoji fallback will handle them anyway.

BUG=skia:

Review URL: https://codereview.chromium.org/1380973002
3 files changed