Name core/fxge/android files appropriately and use one file per class

core/fxge/android/fpf_skiamodule.h

-// Copyright 2014 PDFium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
-
-#ifndef CORE_FXGE_ANDROID_FPF_SKIAMODULE_H_
-#define CORE_FXGE_ANDROID_FPF_SKIAMODULE_H_
-
-#include "core/fxcrt/fx_system.h"
-
-#if _FX_OS_ == _FX_ANDROID_
-
-#include "core/fxge/android/fpf_skiafontmgr.h"
-
-class CFPF_SkiaFontMgr;
-
-class CFPF_SkiaDeviceModule {
- public:
-  CFPF_SkiaDeviceModule() : m_pFontMgr(nullptr) {}
-  ~CFPF_SkiaDeviceModule();
-
-  void Destroy();
-  CFPF_SkiaFontMgr* GetFontMgr();
-
- protected:
-  CFPF_SkiaFontMgr* m_pFontMgr;
-};
-
-CFPF_SkiaDeviceModule* CFPF_GetSkiaDeviceModule();
-
-#endif  // _FX_OS_ == _FX_ANDROID_
-
-#endif  // CORE_FXGE_ANDROID_FPF_SKIAMODULE_H_