Ignore the default zoom level for the PDF extension and print preview.

chrome/browser/printing/print_preview_dialog_controller.cc

 // 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.
 
 #include "chrome/browser/printing/print_preview_dialog_controller.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 10 matching lines @@
 #include "chrome/browser/ui/browser_navigator.h"
 #include "chrome/browser/ui/browser_window.h"
 #include "chrome/browser/ui/host_desktop.h"
 #include "chrome/browser/ui/webui/chrome_web_contents_handler.h"
 #include "chrome/browser/ui/webui/constrained_web_dialog_ui.h"
 #include "chrome/browser/ui/webui/print_preview/print_preview_ui.h"
 #include "chrome/common/chrome_content_client.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/url_constants.h"
 #include "components/web_modal/web_contents_modal_dialog_host.h"
+#include "content/public/browser/host_zoom_map.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_source.h"
 #include "content/public/browser/plugin_service.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
@@ skipping 336 matching lines @@
     WebContents* initiator) {
   base::AutoReset<bool> auto_reset(&is_creating_print_preview_dialog_, true);
 
   // The dialog delegates are deleted when the dialog is closed.
   ConstrainedWebDialogDelegate* web_dialog_delegate =
       ShowConstrainedWebDialog(initiator->GetBrowserContext(),
                                new PrintPreviewDialogDelegate(initiator),
                                initiator);
 
   WebContents* preview_dialog = web_dialog_delegate->GetWebContents();
+  GURL print_url(chrome::kChromeUIPrintURL);
+  content::HostZoomMap::Get(preview_dialog->GetSiteInstance())
+      ->SetZoomLevelForHostAndScheme(print_url.scheme(), print_url.host(), 0);
   EnableInternalPDFPluginForContents(preview_dialog);
   PrintViewManager::CreateForWebContents(preview_dialog);
   extensions::ChromeExtensionWebContentsObserver::CreateForWebContents(
       preview_dialog);
 
   // Add an entry to the map.
   preview_dialog_map_[preview_dialog] = initiator;
   waiting_for_new_preview_page_ = true;
 
   AddObservers(initiator);
@@ skipping 84 matching lines @@
         static_cast<PrintPreviewUI*>(web_ui->GetController());
     if (print_preview_ui)
       print_preview_ui->OnPrintPreviewDialogDestroyed();
   }
 
   preview_dialog_map_.erase(preview_dialog);
   RemoveObservers(preview_dialog);
 }
 
 }  // namespace printing