Refactor pdf_to_emf_converter

chrome/browser/printing/pdf_to_emf_converter.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 "chrome/browser/printing/pdf_to_emf_converter.h"
 
 #include <stdint.h>
 #include <windows.h>
 
 #include <memory>
@@ skipping 12 matching lines @@
 #include "chrome/common/chrome_utility_printing_messages.h"
 #include "chrome/grit/generated_resources.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/child_process_data.h"
 #include "content/public/browser/utility_process_host.h"
 #include "content/public/browser/utility_process_host_client.h"
 #include "printing/emf_win.h"
 #include "printing/pdf_render_settings.h"
 #include "ui/base/l10n/l10n_util.h"
 
+using content::BrowserThread;
+
 namespace printing {
 
 namespace {
 
-using content::BrowserThread;
-
-class PdfToEmfConverterImpl;
+class PdfConverterImpl;
 
 // Allows to delete temporary directory after all temporary files created inside
 // are closed. Windows cannot delete directory with opened files. Directory is
 // used to store PDF and metafiles. PDF should be gone by the time utility
 // process exits. Metafiles should be gone when all LazyEmf destroyed.
 class RefCountedTempDir
     : public base::RefCountedThreadSafe<RefCountedTempDir,
                                         BrowserThread::DeleteOnFileThread> {
  public:
   RefCountedTempDir() { ignore_result(temp_dir_.CreateUniqueTempDir()); }
   bool IsValid() const { return temp_dir_.IsValid(); }
   const base::FilePath& GetPath() const { return temp_dir_.GetPath(); }
 
  private:
   friend struct BrowserThread::DeleteOnThread<BrowserThread::FILE>;
   friend class base::DeleteHelper<RefCountedTempDir>;
   ~RefCountedTempDir() {}
 
   base::ScopedTempDir temp_dir_;
   DISALLOW_COPY_AND_ASSIGN(RefCountedTempDir);
 };
 
-typedef std::unique_ptr<base::File, BrowserThread::DeleteOnFileThread>
-    ScopedTempFile;
+using ScopedTempFile =
+    std::unique_ptr<base::File, BrowserThread::DeleteOnFileThread>;
 
 // Wrapper for Emf to keep only file handle in memory, and load actual data only
 // on playback. Emf::InitFromFile() can play metafile directly from disk, but it
 // can't open file handles. We need file handles to reliably delete temporary
 // files, and to efficiently interact with utility process.
 class LazyEmf : public MetafilePlayer {
  public:
   LazyEmf(const scoped_refptr<RefCountedTempDir>& temp_dir, ScopedTempFile file)
       : temp_dir_(temp_dir), file_(std::move(file)) {
     CHECK(file_);
   }
   ~LazyEmf() override { Close(); }
 
+ protected:
+  // MetafilePlayer:
   bool SafePlayback(HDC hdc) const override;
-  bool GetDataAsVector(std::vector<char>* buffer) const override;
-  bool SaveTo(base::File* file) const override;
 
- private:
   void Close() const;
   bool LoadEmf(Emf* emf) const;
 
+ private:
   mutable scoped_refptr<RefCountedTempDir> temp_dir_;
   mutable ScopedTempFile file_;  // Mutable because of consts in base class.
 
+  bool GetDataAsVector(std::vector<char>* buffer) const override;
+  bool SaveTo(base::File* file) const override;
+
   DISALLOW_COPY_AND_ASSIGN(LazyEmf);
 };
 
-// Converts PDF into EMF.
+class PdfConverterUtilityProcessHostClient
+    : public content::UtilityProcessHostClient {

[Vitaly Buka (NO REVIEWS), 2017/01/19 00:35:09]

Class comments should go before class, not inside.

[rbpotter, 2017/01/19 02:46:15]

Done.

+// Class for converting PDF to another format for printing (Emf, Postscript).
 // Class uses 3 threads: UI, IO and FILE.
 // Internal workflow is following:
 // 1. Create instance on the UI thread. (files_, settings_,)
 // 2. Create pdf file on the FILE thread.
 // 3. Start utility process and start conversion on the IO thread.
 // 4. Utility process returns page count.
 // 5. For each page:
 //   1. Clients requests page with file handle to a temp file.
 //   2. Utility converts the page, save it to the file and reply.
 //
 // All these steps work sequentially, so no data should be accessed
 // simultaneously by several threads.
-class PdfToEmfUtilityProcessHostClient
-    : public content::UtilityProcessHostClient {
  public:

[Vitaly Buka (NO REVIEWS), 2017/01/19 00:35:09]

CL needs "git cl format"

[rbpotter, 2017/01/19 02:46:15]

Done.

-  PdfToEmfUtilityProcessHostClient(
-      base::WeakPtr<PdfToEmfConverterImpl> converter,
+  PdfConverterUtilityProcessHostClient(
+      base::WeakPtr<PdfConverterImpl> converter,
       const PdfRenderSettings& settings);
 
   void Start(const scoped_refptr<base::RefCountedMemory>& data,
              bool print_text_with_gdi,
-             const PdfToEmfConverter::StartCallback& start_callback);
+             const PdfConverter::StartCallback& start_callback);
 
   void GetPage(int page_number,
-               const PdfToEmfConverter::GetPageCallback& get_page_callback);
+               const PdfConverter::GetPageCallback& get_page_callback);
 
   void Stop();
 
+  // UtilityProcessHostClient implementation.
+  void OnProcessCrashed(int exit_code) override;
+  void OnProcessLaunchFailed(int exit_code) override;
+
   // Needs to be public to handle ChromeUtilityHostMsg_PreCacheFontCharacters
   // sync message replies.
   bool Send(IPC::Message* msg);
-
-  // UtilityProcessHostClient implementation.
-  void OnProcessCrashed(int exit_code) override;
-  void OnProcessLaunchFailed(int exit_code) override;
-  bool OnMessageReceived(const IPC::Message& message) override;
-
- private:
+ protected:
   class GetPageCallbackData {
    public:
     GetPageCallbackData(int page_number,
-                        PdfToEmfConverter::GetPageCallback callback)
+                        PdfConverter::GetPageCallback callback)
         : page_number_(page_number), callback_(callback) {}
 
     GetPageCallbackData(GetPageCallbackData&& other) {
       *this = std::move(other);
     }
 
     GetPageCallbackData& operator=(GetPageCallbackData&& rhs) {
       page_number_ = rhs.page_number_;
       callback_ = rhs.callback_;
-      emf_ = std::move(rhs.emf_);
+      file_ = std::move(rhs.file_);
       return *this;
     }
 
     int page_number() const { return page_number_; }
-    const PdfToEmfConverter::GetPageCallback& callback() const {
+    const PdfConverter::GetPageCallback& callback() const {
       return callback_;
     }
-    ScopedTempFile TakeEmf() { return std::move(emf_); }
-    void set_emf(ScopedTempFile emf) { emf_ = std::move(emf); }
+    ScopedTempFile TakeFile() { return std::move(file_); }
+    void set_file(ScopedTempFile file) { file_ = std::move(file); }
 
    private:
     int page_number_;
-    PdfToEmfConverter::GetPageCallback callback_;
-    ScopedTempFile emf_;
+
+    PdfConverter::GetPageCallback callback_;
+    ScopedTempFile file_;
 
     DISALLOW_COPY_AND_ASSIGN(GetPageCallbackData);
   };
 
-  ~PdfToEmfUtilityProcessHostClient() override;
+  ~PdfConverterUtilityProcessHostClient() {}
 
-  // Message handlers.
+  // Helper functions: must be overridden by subclasses
+  // Set the process name
+  virtual base::string16 GetName() const = 0;
+  // Create a metafileplayer subclass file from a temporary file.
+  virtual std::unique_ptr<MetafilePlayer> GetFileFromTemp(
+      std::unique_ptr<base::File,
+      content::BrowserThread::DeleteOnFileThread> temp_file) = 0;
+  // Send the messages to Start, GetPage, and Stop.
+  virtual void SendStartMessage(IPC::PlatformFileForTransit transit,
+                                bool print_text_with_gdi) = 0;
+  virtual void SendGetPageMessage(int page_number,
+                                  IPC::PlatformFileForTransit transit) = 0;
+  virtual void SendStopMessage() = 0;
+
+  // Message handlers:
   void OnPageCount(int page_count);
   void OnPageDone(bool success, float scale_factor);
-  void OnPreCacheFontCharacters(const LOGFONT& log_font,
-                                const base::string16& characters);
 
   void OnFailed();
+  void OnTempFileReady(GetPageCallbackData* callback_data,
+                       ScopedTempFile temp_file);
   void OnTempPdfReady(bool print_text_with_gdi, ScopedTempFile pdf);
-  void OnTempEmfReady(GetPageCallbackData* callback_data, ScopedTempFile emf);
 
   scoped_refptr<RefCountedTempDir> temp_dir_;
 
-  // Used to suppress callbacks after PdfToEmfConverterImpl is deleted.
-  base::WeakPtr<PdfToEmfConverterImpl> converter_;
+  // Used to suppress callbacks after PdfConverter is deleted.
+  base::WeakPtr<PdfConverterImpl> converter_;
   PdfRenderSettings settings_;
 
   // Document loaded callback.
-  PdfToEmfConverter::StartCallback start_callback_;
+  PdfConverter::StartCallback start_callback_;
 
   // Process host for IPC.
   base::WeakPtr<content::UtilityProcessHost> utility_process_host_;
 
   // Queue of callbacks for GetPage() requests. Utility process should reply
   // with PageDone in the same order as requests were received.
   // Use containers that keeps element pointers valid after push() and pop().
-  typedef std::queue<GetPageCallbackData> GetPageCallbacks;
+  using GetPageCallbacks = std::queue<GetPageCallbackData>;
   GetPageCallbacks get_page_callbacks_;
+};
+
+// Converts PDF into Emf.
+class PdfToEmfUtilityProcessHostClient
+    : public PdfConverterUtilityProcessHostClient {
+ public:
+  PdfToEmfUtilityProcessHostClient(
+      base::WeakPtr<PdfConverterImpl> converter,
+      const PdfRenderSettings& settings)
+      : PdfConverterUtilityProcessHostClient(converter, settings) {}
+
+  bool OnMessageReceived(const IPC::Message& message) override;
+
+ private:
+  // Helpers to send messages and set process name
+  base::string16 GetName() const override;
+  std::unique_ptr<MetafilePlayer> GetFileFromTemp(
+      std::unique_ptr<base::File,
+                      content::BrowserThread::DeleteOnFileThread> temp_file)
+      override;
+  void SendStartMessage(IPC::PlatformFileForTransit transit,
+                        bool print_text_with_gdi) override;
+  void SendGetPageMessage(int page_number,
+                          IPC::PlatformFileForTransit transit) override;
+  void SendStopMessage() override;
+
+  // Additional message handler needed for Pdf to Emf
+  void OnPreCacheFontCharacters(const LOGFONT& log_font,
+                                const base::string16& characters);
 
   DISALLOW_COPY_AND_ASSIGN(PdfToEmfUtilityProcessHostClient);
 };
 
-class PdfToEmfConverterImpl : public PdfToEmfConverter {
+class PdfConverterImpl: public PdfConverter {
  public:
-  PdfToEmfConverterImpl();
+  PdfConverterImpl();
 
-  ~PdfToEmfConverterImpl() override;
+  ~PdfConverterImpl() override;
 
   void Start(const scoped_refptr<base::RefCountedMemory>& data,
              const PdfRenderSettings& conversion_settings,
              bool print_text_with_gdi,
              const StartCallback& start_callback) override;
 
   void GetPage(int page_number,
                const GetPageCallback& get_page_callback) override;
 
   // Helps to cancel callbacks if this object is destroyed.
   void RunCallback(const base::Closure& callback);
 
+ protected:
+  scoped_refptr<PdfConverterUtilityProcessHostClient> utility_client_;
+
  private:
-  scoped_refptr<PdfToEmfUtilityProcessHostClient> utility_client_;
+  DISALLOW_COPY_AND_ASSIGN(PdfConverterImpl);
+};
+
+class PdfToEmfConverterImpl : public PdfConverterImpl {
+ public:
+  PdfToEmfConverterImpl();
+
+  ~PdfToEmfConverterImpl() {}
+
+  void Start(const scoped_refptr<base::RefCountedMemory>& data,
+             const PdfRenderSettings& conversion_settings,
+             bool print_text_with_gdi,
+             const StartCallback& start_callback) override;
+
+ private:
   base::WeakPtrFactory<PdfToEmfConverterImpl> weak_ptr_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(PdfToEmfConverterImpl);
 };
 
 ScopedTempFile CreateTempFile(scoped_refptr<RefCountedTempDir>* temp_dir) {
   if (!temp_dir->get())
     *temp_dir = new RefCountedTempDir();
   ScopedTempFile file;
   if (!(*temp_dir)->IsValid())
     return file;
   base::FilePath path;
@@ skipping 27 matching lines @@
     pdf_file.reset();
     return pdf_file;
   }
   pdf_file->Seek(base::File::FROM_BEGIN, 0);
   return pdf_file;
 }
 
 bool LazyEmf::SafePlayback(HDC hdc) const {
   Emf emf;
   bool result = LoadEmf(&emf) && emf.SafePlayback(hdc);
-  // TODO(vitalybuka): Fix destruction of metafiles. For some reasons
-  // instances of Emf are not deleted. crbug.com/411683
+  // TODO(thestig): Fix destruction of metafiles. For some reasons
+  // instances of Emf are not deleted. https://crbug.com/260806
   // It's known that the Emf going to be played just once to a printer. So just
-  // release file here.
+  // release |file_| here.
   Close();
   return result;
 }
 
 bool LazyEmf::GetDataAsVector(std::vector<char>* buffer) const {
   NOTREACHED();
   return false;
 }
 
 bool LazyEmf::SaveTo(base::File* file) const {
   Emf emf;
   return LoadEmf(&emf) && emf.SaveTo(file);
 }
 
 void LazyEmf::Close() const {
   file_.reset();
-  temp_dir_ = NULL;
+  temp_dir_ = nullptr;
 }
 
 bool LazyEmf::LoadEmf(Emf* emf) const {
   file_->Seek(base::File::FROM_BEGIN, 0);
   int64_t size = file_->GetLength();
   if (size <= 0)
     return false;
   std::vector<char> data(size);
   if (file_->ReadAtCurrentPos(data.data(), data.size()) != size)
     return false;
   return emf->InitFromData(data.data(), data.size());
 }
 
-PdfToEmfUtilityProcessHostClient::PdfToEmfUtilityProcessHostClient(
-    base::WeakPtr<PdfToEmfConverterImpl> converter,
+PdfConverterUtilityProcessHostClient::PdfConverterUtilityProcessHostClient(
+    base::WeakPtr<PdfConverterImpl> converter,
     const PdfRenderSettings& settings)
     : converter_(converter), settings_(settings) {
 }
 
-PdfToEmfUtilityProcessHostClient::~PdfToEmfUtilityProcessHostClient() {
+void PdfConverterUtilityProcessHostClient::OnPageCount(int page_count) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (start_callback_.is_null())
+    return OnFailed();
+  BrowserThread::PostTask(BrowserThread::UI,
+                          FROM_HERE,
+                          base::Bind(&PdfConverterImpl::RunCallback,
+                                     converter_,
+                                     base::Bind(start_callback_, page_count)));
+  start_callback_.Reset();
 }
 
-void PdfToEmfUtilityProcessHostClient::Start(
+void PdfConverterUtilityProcessHostClient::OnPageDone(bool success,
+                                                      float scale_factor) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (get_page_callbacks_.empty())
+    return OnFailed();
+  GetPageCallbackData& data = get_page_callbacks_.front();
+  std::unique_ptr<MetafilePlayer> file;
+
+  if (success) {
+    ScopedTempFile temp_file = data.TakeFile();
+    if (!temp_file)  // Unexpected message from utility process.
+      return OnFailed();
+    file = GetFileFromTemp(std::move(temp_file));
+  }
+
+  BrowserThread::PostTask(BrowserThread::UI,
+                          FROM_HERE,
+                          base::Bind(&PdfConverterImpl::RunCallback,
+                                     converter_,
+                                     base::Bind(data.callback(),
+                                                data.page_number(),
+                                                scale_factor,
+                                                base::Passed(&file))));
+  get_page_callbacks_.pop();
+}
+
+void PdfConverterUtilityProcessHostClient::OnProcessCrashed(int exit_code) {
+  OnFailed();
+}
+
+void PdfConverterUtilityProcessHostClient::OnProcessLaunchFailed(
+    int exit_code) {
+  OnFailed();
+}
+
+bool PdfConverterUtilityProcessHostClient::Send(IPC::Message* msg) {
+  if (utility_process_host_)
+    return utility_process_host_->Send(msg);
+  delete msg;
+  return false;
+}
+
+void PdfConverterUtilityProcessHostClient::Start(
     const scoped_refptr<base::RefCountedMemory>& data,
     bool print_text_with_gdi,
-    const PdfToEmfConverter::StartCallback& start_callback) {
+    const PdfConverter::StartCallback& start_callback) {
   if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
-    BrowserThread::PostTask(
-        BrowserThread::IO, FROM_HERE,
-        base::Bind(&PdfToEmfUtilityProcessHostClient::Start, this, data,
-                   print_text_with_gdi, start_callback));
+    BrowserThread::PostTask(BrowserThread::IO, FROM_HERE,
+        base::Bind(&PdfConverterUtilityProcessHostClient::Start,
+                   this, data, print_text_with_gdi, start_callback));
     return;
   }
 
   // Store callback before any OnFailed() call to make it called on failure.
   start_callback_ = start_callback;
 
   // NOTE: This process _must_ be sandboxed, otherwise the pdf dll will load
   // gdiplus.dll, change how rendering happens, and not be able to correctly
   // generate when sent to a metafile DC.
   utility_process_host_ = content::UtilityProcessHost::Create(
                               this, base::ThreadTaskRunnerHandle::Get())
                               ->AsWeakPtr();
-  utility_process_host_->SetName(l10n_util::GetStringUTF16(
-      IDS_UTILITY_PROCESS_EMF_CONVERTOR_NAME));
+  utility_process_host_->SetName(GetName());
 
   BrowserThread::PostTaskAndReplyWithResult(
       BrowserThread::FILE, FROM_HERE,
       base::Bind(&CreateTempPdfFile, data, &temp_dir_),
-      base::Bind(&PdfToEmfUtilityProcessHostClient::OnTempPdfReady, this,
+      base::Bind(&PdfConverterUtilityProcessHostClient::OnTempPdfReady, this,
                  print_text_with_gdi));
 }
 
-void PdfToEmfUtilityProcessHostClient::OnTempPdfReady(bool print_text_with_gdi,
-                                                      ScopedTempFile pdf) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  if (!utility_process_host_ || !pdf)
-    return OnFailed();
-  // Should reply with OnPageCount().
-  Send(new ChromeUtilityMsg_RenderPDFPagesToMetafiles(
-      IPC::GetPlatformFileForTransit(pdf->GetPlatformFile(), false), settings_,
-      print_text_with_gdi));
-}
-
-void PdfToEmfUtilityProcessHostClient::OnPageCount(int page_count) {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  if (start_callback_.is_null())
-    return OnFailed();
-  BrowserThread::PostTask(BrowserThread::UI,
-                          FROM_HERE,
-                          base::Bind(&PdfToEmfConverterImpl::RunCallback,
-                                     converter_,
-                                     base::Bind(start_callback_, page_count)));
-  start_callback_.Reset();
-}
-
-void PdfToEmfUtilityProcessHostClient::GetPage(
+void PdfConverterUtilityProcessHostClient::GetPage(
     int page_number,
-    const PdfToEmfConverter::GetPageCallback& get_page_callback) {
+    const PdfConverter::GetPageCallback& get_page_callback) {
   if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
     BrowserThread::PostTask(
         BrowserThread::IO,
         FROM_HERE,
-        base::Bind(&PdfToEmfUtilityProcessHostClient::GetPage,
+        base::Bind(&PdfConverterUtilityProcessHostClient::GetPage,
                    this,
                    page_number,
                    get_page_callback));
     return;
   }
 
   // Store callback before any OnFailed() call to make it called on failure.
   get_page_callbacks_.push(GetPageCallbackData(page_number, get_page_callback));
 
   if (!utility_process_host_)
     return OnFailed();
 
   BrowserThread::PostTaskAndReplyWithResult(
       BrowserThread::FILE,
       FROM_HERE,
       base::Bind(&CreateTempFile, &temp_dir_),
-      base::Bind(&PdfToEmfUtilityProcessHostClient::OnTempEmfReady,
+      base::Bind(&PdfConverterUtilityProcessHostClient::OnTempFileReady,
                  this,
                  &get_page_callbacks_.back()));
 }
 
-void PdfToEmfUtilityProcessHostClient::OnTempEmfReady(
+void PdfConverterUtilityProcessHostClient::OnTempFileReady(
     GetPageCallbackData* callback_data,
-    ScopedTempFile emf) {
+    ScopedTempFile temp_file) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  if (!utility_process_host_ || !emf)
+  if (!utility_process_host_ || !temp_file)
     return OnFailed();
   IPC::PlatformFileForTransit transit =
-      IPC::GetPlatformFileForTransit(emf->GetPlatformFile(), false);
-  callback_data->set_emf(std::move(emf));
+      IPC::GetPlatformFileForTransit(temp_file->GetPlatformFile(), false);
+  callback_data->set_file(std::move(temp_file));
   // Should reply with OnPageDone().
-  Send(new ChromeUtilityMsg_RenderPDFPagesToMetafiles_GetPage(
-      callback_data->page_number(), transit));
+  SendGetPageMessage(callback_data->page_number(), transit);
 }
 
-void PdfToEmfUtilityProcessHostClient::OnPageDone(bool success,
-                                                  float scale_factor) {
+void PdfConverterUtilityProcessHostClient::OnTempPdfReady(
+    bool print_text_with_gdi,
+    ScopedTempFile pdf) {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  if (get_page_callbacks_.empty())
+  if (!utility_process_host_ || !pdf)
     return OnFailed();
-  GetPageCallbackData& data = get_page_callbacks_.front();
-  std::unique_ptr<MetafilePlayer> emf;
+  // Should reply with OnPageCount().
+  SendStartMessage(IPC::GetPlatformFileForTransit(pdf->GetPlatformFile(),
+                                                  false), print_text_with_gdi);
+}
 
-  if (success) {
-    ScopedTempFile temp_emf = data.TakeEmf();
-    if (!temp_emf)  // Unexpected message from utility process.
-      return OnFailed();
-    emf = base::MakeUnique<LazyEmf>(temp_dir_, std::move(temp_emf));
+void PdfConverterUtilityProcessHostClient::Stop() {
+  if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
+    BrowserThread::PostTask(
+        BrowserThread::IO,
+        FROM_HERE,
+        base::Bind(&PdfToEmfUtilityProcessHostClient::Stop, this));
+    return;
   }
+  SendStopMessage();
+}
 
-  BrowserThread::PostTask(BrowserThread::UI,
-                          FROM_HERE,
-                          base::Bind(&PdfToEmfConverterImpl::RunCallback,
-                                     converter_,
-                                     base::Bind(data.callback(),
-                                                data.page_number(),
-                                                scale_factor,
-                                                base::Passed(&emf))));
-  get_page_callbacks_.pop();
+void PdfConverterUtilityProcessHostClient::OnFailed() {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  if (!start_callback_.is_null())
+    OnPageCount(0);
+  while (!get_page_callbacks_.empty())
+    OnPageDone(false, 0.0f);
+  utility_process_host_.reset();
+}
+
+// Pdf to Emf
+bool PdfToEmfUtilityProcessHostClient::OnMessageReceived(
+    const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(PdfToEmfUtilityProcessHostClient, message)
+    IPC_MESSAGE_HANDLER(
+        ChromeUtilityHostMsg_RenderPDFPagesToMetafiles_PageCount, OnPageCount)
+    IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_RenderPDFPagesToMetafiles_PageDone,
+                        OnPageDone)
+    IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_PreCacheFontCharacters,
+                        OnPreCacheFontCharacters)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+base::string16 PdfToEmfUtilityProcessHostClient::GetName() const {
+  return l10n_util::GetStringUTF16(IDS_UTILITY_PROCESS_EMF_CONVERTOR_NAME);
+}
+
+std::unique_ptr<MetafilePlayer>
+PdfToEmfUtilityProcessHostClient::GetFileFromTemp(
+    std::unique_ptr<base::File,
+    content::BrowserThread::DeleteOnFileThread> temp_file) {
+  return base::MakeUnique<LazyEmf>(temp_dir_, std::move(temp_file));
+}
+
+void PdfToEmfUtilityProcessHostClient::SendGetPageMessage(
+    int page_number, IPC::PlatformFileForTransit transit) {
+  Send(new ChromeUtilityMsg_RenderPDFPagesToMetafiles_GetPage(page_number,
+                                                              transit));
+}
+
+void PdfToEmfUtilityProcessHostClient::SendStartMessage(
+    IPC::PlatformFileForTransit transit,
+    bool print_text_with_gdi) {
+  Send(new ChromeUtilityMsg_RenderPDFPagesToMetafiles(transit,
+                                                      settings_,
+                                                      print_text_with_gdi));
+}
+
+void PdfToEmfUtilityProcessHostClient::SendStopMessage() {
+  Send(new ChromeUtilityMsg_RenderPDFPagesToMetafiles_Stop());
 }
 
 void PdfToEmfUtilityProcessHostClient::OnPreCacheFontCharacters(
     const LOGFONT& font,
     const base::string16& str) {
   // TODO(scottmg): pdf/ppapi still require the renderer to be able to precache
   // GDI fonts (http://crbug.com/383227), even when using DirectWrite.
   // Eventually this shouldn't be added and should be moved to
   // FontCacheDispatcher too. http://crbug.com/356346.
 
@@ skipping 14 matching lines @@
 
   SelectObject(hdc, old_font);
   DeleteObject(font_handle);
 
   HENHMETAFILE metafile = CloseEnhMetaFile(hdc);
 
   if (metafile)
     DeleteEnhMetaFile(metafile);
 }
 
-void PdfToEmfUtilityProcessHostClient::Stop() {
-  if (!BrowserThread::CurrentlyOn(BrowserThread::IO)) {
-    BrowserThread::PostTask(
-        BrowserThread::IO,
-        FROM_HERE,
-        base::Bind(&PdfToEmfUtilityProcessHostClient::Stop, this));
-    return;
-  }
-  Send(new ChromeUtilityMsg_RenderPDFPagesToMetafiles_Stop());
+// Pdf Converter Impl and subclasses
+PdfConverterImpl::PdfConverterImpl() {
 }
 
-void PdfToEmfUtilityProcessHostClient::OnProcessCrashed(int exit_code) {
-  OnFailed();
+PdfConverterImpl::~PdfConverterImpl() {
+  if (utility_client_.get())
+    utility_client_->Stop();
 }
 
-void PdfToEmfUtilityProcessHostClient::OnProcessLaunchFailed(int exit_code) {
-  OnFailed();
+void PdfConverterImpl::Start(
+    const scoped_refptr<base::RefCountedMemory>& data,
+    const PdfRenderSettings& conversion_settings,
+    bool print_text_with_gdi,
+    const StartCallback& start_callback) {
+  DCHECK(!utility_client_.get());
 }
 
-bool PdfToEmfUtilityProcessHostClient::OnMessageReceived(
-    const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(PdfToEmfUtilityProcessHostClient, message)
-    IPC_MESSAGE_HANDLER(
-        ChromeUtilityHostMsg_RenderPDFPagesToMetafiles_PageCount, OnPageCount)
-    IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_RenderPDFPagesToMetafiles_PageDone,
-                        OnPageDone)
-    IPC_MESSAGE_HANDLER(ChromeUtilityHostMsg_PreCacheFontCharacters,
-                        OnPreCacheFontCharacters)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
+void PdfConverterImpl::GetPage(int page_number,
+                                    const GetPageCallback& get_page_callback) {
+  utility_client_->GetPage(page_number, get_page_callback);
 }
 
-bool PdfToEmfUtilityProcessHostClient::Send(IPC::Message* msg) {
-  if (utility_process_host_)
-    return utility_process_host_->Send(msg);
-  delete msg;
-  return false;
-}
-
-void PdfToEmfUtilityProcessHostClient::OnFailed() {
-  DCHECK_CURRENTLY_ON(BrowserThread::IO);
-  if (!start_callback_.is_null())
-    OnPageCount(0);
-  while (!get_page_callbacks_.empty())
-    OnPageDone(false, 0.0f);
-  utility_process_host_.reset();
+void PdfConverterImpl::RunCallback(const base::Closure& callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  callback.Run();
 }
 
 PdfToEmfConverterImpl::PdfToEmfConverterImpl() : weak_ptr_factory_(this) {
 }
 
-PdfToEmfConverterImpl::~PdfToEmfConverterImpl() {
-  if (utility_client_.get())
-    utility_client_->Stop();
-}
-
 void PdfToEmfConverterImpl::Start(
     const scoped_refptr<base::RefCountedMemory>& data,
     const PdfRenderSettings& conversion_settings,
     bool print_text_with_gdi,
     const StartCallback& start_callback) {
   DCHECK(!utility_client_.get());
   utility_client_ = new PdfToEmfUtilityProcessHostClient(
       weak_ptr_factory_.GetWeakPtr(), conversion_settings);
   utility_client_->Start(data, print_text_with_gdi, start_callback);
 }
 
-void PdfToEmfConverterImpl::GetPage(int page_number,
-                                    const GetPageCallback& get_page_callback) {
-  utility_client_->GetPage(page_number, get_page_callback);
-}
-
-void PdfToEmfConverterImpl::RunCallback(const base::Closure& callback) {
-  DCHECK_CURRENTLY_ON(BrowserThread::UI);
-  callback.Run();
-}
-
 }  // namespace
 
-PdfToEmfConverter::~PdfToEmfConverter() {
-}
+PdfConverter::~PdfConverter() {}
 
 // static
-std::unique_ptr<PdfToEmfConverter> PdfToEmfConverter::CreateDefault() {
-  return std::unique_ptr<PdfToEmfConverter>(new PdfToEmfConverterImpl());
+std::unique_ptr<PdfConverter> PdfConverter::CreatePdfToEmfConverter() {
+  return base::MakeUnique<PdfToEmfConverterImpl>();
 }
-
 }  // namespace printing