[pdf] Reset defer_page_unload to original value.

pdf/pdfium/pdfium_engine.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 "pdf/pdfium/pdfium_engine.h"
 
 #include <math.h>
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 2452 matching lines @@
 }
 
 int PDFiumEngine::GetMostVisiblePage() {
   if (in_flight_visible_page_)
     return *in_flight_visible_page_;
 
   // We can call GetMostVisiblePage through a callback from PDFium. We have
   // to defer the page deletion otherwise we could potentially delete the page
   // that originated the calling JS request and destroy the objects that are
   // currently being used.
+  bool old_defer_page_unload = defer_page_unload_;

[Tom Sepez, 2016/12/05 17:54:05]

base::AutoReset maybe?

[dsinclair, 2016/12/05 20:07:48]

Done.

   defer_page_unload_ = true;
   CalculateVisiblePages();
-  defer_page_unload_ = false;
+  defer_page_unload_ = old_defer_page_unload;
   return most_visible_page_;
 }
 
 pp::Rect PDFiumEngine::GetPageRect(int index) {
   pp::Rect rc(pages_[index]->rect());
   rc.Inset(-kPageShadowLeft, -kPageShadowTop,
            -kPageShadowRight, -kPageShadowBottom);
   return rc;
 }
 
@@ skipping 1667 matching lines @@
 
 bool PDFiumEngineExports::GetPDFPageSizeByIndex(void* pdf_handle,
                                                 int page_number,
                                                 double* width,
                                                 double* height) {
   FPDF_DOCUMENT doc = pdf_handle;
   return doc && FPDF_GetPageSizeByIndex(doc, page_number, width, height) != 0;
 }
 
 }  // namespace chrome_pdf