Make printing work better with OOPIF.

android_webview/browser/aw_print_manager.h

 // Copyright 2015 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 ANDROID_WEBVIEW_BROWSER_PRINT_MANAGER_H_
-#define ANDROID_WEBVIEW_BROWSER_PRINT_MANAGER_H_
+#ifndef ANDROID_WEBVIEW_BROWSER_AW_PRINT_MANAGER_H_
+#define ANDROID_WEBVIEW_BROWSER_AW_PRINT_MANAGER_H_
 
 #include "base/macros.h"
 #include "components/printing/browser/print_manager.h"
 #include "content/public/browser/web_contents_user_data.h"
 #include "printing/print_settings.h"
 
 namespace android_webview {
 
 class AwPrintManager : public printing::PrintManager,
     public content::WebContentsUserData<AwPrintManager> {
  public:
-  // Creates a AwPrintManager for the provided webcontents. If the
+  // Creates an AwPrintManager for the provided WebContents. If the
   // AwPrintManager already exists, it is destroyed and a new one is created.
   static AwPrintManager* CreateForWebContents(
       content::WebContents* contents,
       const printing::PrintSettings& settings,
       const base::FileDescriptor& file_descriptor,
       const PdfWritingDoneCallback& callback);
 
   ~AwPrintManager() override;
 
   bool PrintNow();
 
  private:
   friend class content::WebContentsUserData<AwPrintManager>;
+
   AwPrintManager(content::WebContents* contents,
                  const printing::PrintSettings& settings,
                  const base::FileDescriptor& file_descriptor,
                  const PdfWritingDoneCallback& callback);
 
-  bool OnMessageReceived(const IPC::Message& message) override;
+  // printing::PrintManager:
+  bool OnMessageReceived(const IPC::Message& message,
+                         content::RenderFrameHost* render_frame_host) override;
+
+  // IPC Handlers
   void OnGetDefaultPrintSettings(IPC::Message* reply_msg);
 
   printing::PrintSettings settings_;
 
   DISALLOW_COPY_AND_ASSIGN(AwPrintManager);
 };
 
 }  // namespace android_webview
 
-#endif  // ANDROID_WEBVIEW_BROWSER_PRINT_MANAGER_H_
+#endif  // ANDROID_WEBVIEW_BROWSER_AW_PRINT_MANAGER_H_