Unify the three places that patch font loading for PDFium on Windows.

content/child/child_thread_impl.h

 // Copyright (c) 2012 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.
 
-#ifndef CONTENT_CHILD_CHILD_THREAD_H_
-#define CONTENT_CHILD_CHILD_THREAD_H_
+#ifndef CONTENT_CHILD_CHILD_THREAD_IMPL_H_
+#define CONTENT_CHILD_CHILD_THREAD_IMPL_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/shared_memory.h"
 #include "base/memory/weak_ptr.h"
 #include "base/power_monitor/power_monitor.h"
 #include "base/tracked_objects.h"
 #include "content/child/mojo/mojo_application.h"
 #include "content/common/content_export.h"
 #include "content/common/message_router.h"
+#include "content/public/child/child_thread.h"
 #include "ipc/ipc_message.h"  // For IPC_MESSAGE_LOG_ENABLED.
 
 namespace base {
 class MessageLoop;
 
 namespace debug {
 class TraceMemoryController;
 }  // namespace debug
 }  // namespace base
 
@@ skipping 21 matching lines @@
 class PushDispatcher;
 class ServiceWorkerMessageFilter;
 class QuotaDispatcher;
 class QuotaMessageFilter;
 class ResourceDispatcher;
 class ThreadSafeSender;
 class WebSocketDispatcher;
 struct RequestInfo;
 
 // The main thread of a child process derives from this class.
-class CONTENT_EXPORT ChildThread : public IPC::Listener, public IPC::Sender {
+class CONTENT_EXPORT ChildThreadImpl
+    : public IPC::Listener,
+      virtual public ChildThread {

[scottmg, 2015/02/03 17:52:06]

Why does this need to be virtual?

[jam, 2015/02/03 18:13:04]

It's because of the diamond inheritance: 

ChildThreadImpl derives from ChildThread
RenderThread derives from ChildThread
RenderThreadImpl derives from RenderThread & ChildThreadImpl

  public:
   struct CONTENT_EXPORT Options {
     Options();
     explicit Options(bool mojo);
     Options(std::string name, bool mojo);
     ~Options();
 
     std::string channel_name;
     bool use_mojo_channel;
     bool in_browser_process;
     std::vector<IPC::MessageFilter*> startup_filters;
   };
 
   // Creates the thread.
-  ChildThread();
+  ChildThreadImpl();
   // Allow to be used for single-process mode and for in process gpu mode via
   // options.
-  explicit ChildThread(const Options& options);
+  explicit ChildThreadImpl(const Options& options);
   // ChildProcess::main_thread() is reset after Shutdown(), and before the
   // destructor, so any subsystem that relies on ChildProcess::main_thread()
   // must be terminated before Shutdown returns. In particular, if a subsystem
   // has a thread that post tasks to ChildProcess::main_thread(), that thread
   // should be joined in Shutdown().
-  ~ChildThread() override;
+  ~ChildThreadImpl() override;
   virtual void Shutdown();
 
   // IPC::Sender implementation:
   bool Send(IPC::Message* msg) override;
 
+  // ChildThread implementation:
+#if defined(OS_WIN)
+  void PreCacheFont(const LOGFONT& log_font) override;
+  void ReleaseCachedFonts() override;
+#endif
+
   IPC::SyncChannel* channel() { return channel_.get(); }
 
   MessageRouter* GetRouter();
 
   // Allocates a block of shared memory of the given size. Returns NULL on
   // failure.
   // Note: On posix, this requires a sync IPC to the browser process,
   // but on windows the child process directly allocates the block.
   scoped_ptr<base::SharedMemory> AllocateSharedMemory(size_t buf_size);
 
@@ skipping 63 matching lines @@
     return quota_message_filter_.get();
   }
 
   ChildResourceMessageFilter* child_resource_message_filter() const {
     return resource_message_filter_.get();
   }
 
   base::MessageLoop* message_loop() const { return message_loop_; }
 
   // Returns the one child thread. Can only be called on the main thread.
-  static ChildThread* current();
+  static ChildThreadImpl* current();
 
 #if defined(OS_ANDROID)
   // Called on Android's service thread to shutdown the main thread of this
   // process.
   static void ShutdownThread();
 #endif
 
   ServiceRegistry* service_registry() const {
     return mojo_application_->service_registry();
   }
@@ skipping 50 matching lines @@
   scoped_ptr<MojoApplication> mojo_application_;
 
   std::string channel_name_;
   scoped_ptr<IPC::SyncChannel> channel_;
 
   // Allows threads other than the main thread to send sync messages.
   scoped_refptr<IPC::SyncMessageFilter> sync_message_filter_;
 
   scoped_refptr<ThreadSafeSender> thread_safe_sender_;
 
-  // Implements message routing functionality to the consumers of ChildThread.
+  // Implements message routing functionality to the consumers of
+  // ChildThreadImpl.
   ChildThreadMessageRouter router_;
 
   // Handles resource loads for this process.
   scoped_ptr<ResourceDispatcher> resource_dispatcher_;
 
   scoped_ptr<WebSocketDispatcher> websocket_dispatcher_;
 
   // The OnChannelError() callback was invoked - the channel is dead, don't
   // attempt to communicate.
   bool on_channel_error_called_;
@@ skipping 30 matching lines @@
   scoped_ptr<base::PowerMonitor> power_monitor_;
 
   scoped_refptr<GeofencingMessageFilter> geofencing_message_filter_;
 
   scoped_refptr<BluetoothMessageFilter> bluetooth_message_filter_;
 
   scoped_refptr<NavigatorConnectDispatcher> navigator_connect_dispatcher_;
 
   bool in_browser_process_;
 
-  base::WeakPtrFactory<ChildThread> channel_connected_factory_;
+  base::WeakPtrFactory<ChildThreadImpl> channel_connected_factory_;
 
-  DISALLOW_COPY_AND_ASSIGN(ChildThread);
+  DISALLOW_COPY_AND_ASSIGN(ChildThreadImpl);
 };
 
 }  // namespace content
 
-#endif  // CONTENT_CHILD_CHILD_THREAD_H_
+#endif  // CONTENT_CHILD_CHILD_THREAD_IMPL_H_