Remove many unused files from //skia/ext

skia/ext/fontmgr_default_win.cc

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "skia/ext/fontmgr_default_win.h"
-
-#include "third_party/skia/include/ports/SkFontMgr.h"
-#include "third_party/skia/include/ports/SkTypeface_win.h"
-
-namespace {
-
-SkFontMgr* g_default_fontmgr;
-
-}  // namespace
-
-void SetDefaultSkiaFactory(SkFontMgr* fontmgr) {
-  g_default_fontmgr = fontmgr;
-}
-
-SK_API SkFontMgr* SkFontMgr::Factory() {
-  // This will be set when DirectWrite is in use, and an SkFontMgr has been
-  // created with the pre-sandbox warmed up one. Otherwise, we fallback to a
-  // GDI SkFontMgr which is used in the browser.
-  if (g_default_fontmgr)
-    return SkRef(g_default_fontmgr);
-  return SkFontMgr_New_GDI();
-}