Use FontPlatformDataHarfBuzz.h on Windows

Merge FontPlatformDataWin.h with FontPlatformDataHarfBuzz.h and use the
same version of the FontPlatformData class defintion/header on Windows
as on linux, chromeos and android.

R=dglazkov@chromium.org
BUG=355806

Review URL: https://codereview.chromium.org/205343010

git-svn-id: svn://svn.chromium.org/blink/trunk@170088 bbb929c8-8fbe-4397-9dbb-9b2b20218538