Remove system call in DW for default font.

The last user of the GDI default font in DW is
onMatchFamilyStyleCharacter and it doesn't appear to actually need
to use it. This change removes a system call, making things a bit
faster, as well as eliminating a call blocked in the sandbox.

BUG=chromium:459056

Review URL: https://codereview.chromium.org/1107283003
2 files changed