Remove fx_fpf.h and IWYU

BUILD.gn

 # Copyright 2016 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.
 
 import("//build_overrides/v8.gni")
 import("//testing/test.gni")
 import("pdfium.gni")
 
 config("pdfium_config") {
   cflags = []
@@ skipping 512 matching lines @@
     "core/src/fxge/agg/src/fx_agg_driver.cpp",
     "core/src/fxge/android/fpf_skiafont.cpp",
     "core/src/fxge/android/fpf_skiafont.h",
     "core/src/fxge/android/fpf_skiafontmgr.cpp",
     "core/src/fxge/android/fpf_skiafontmgr.h",
     "core/src/fxge/android/fpf_skiamodule.cpp",
     "core/src/fxge/android/fpf_skiamodule.h",
     "core/src/fxge/android/fx_android_font.cpp",
     "core/src/fxge/android/fx_android_font.h",
     "core/src/fxge/android/fx_android_imp.cpp",
-    "core/src/fxge/android/fx_fpf.h",
     "core/src/fxge/apple/apple_int.h",
     "core/src/fxge/apple/fx_apple_platform.cpp",
     "core/src/fxge/apple/fx_mac_imp.cpp",
     "core/src/fxge/apple/fx_quartz_device.cpp",
     "core/src/fxge/dib/dib_int.h",
     "core/src/fxge/dib/fx_dib_composite.cpp",
     "core/src/fxge/dib/fx_dib_convert.cpp",
     "core/src/fxge/dib/fx_dib_engine.cpp",
     "core/src/fxge/dib/fx_dib_main.cpp",
     "core/src/fxge/dib/fx_dib_transform.cpp",
@@ skipping 957 matching lines @@
       "//v8:v8_libplatform",
     ]
     include_dirs += [
       "//v8",
       "//v8/include",
     ]
     configs += [ "//v8:external_startup_data" ]
   }
   configs += [ ":pdfium_config" ]
 }