Print Preview: Prevent a crash and add error logging.

chrome/renderer/print_web_view_helper_mac.mm

 // Copyright (c) 2011 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/renderer/print_web_view_helper.h"
 
 #import <AppKit/AppKit.h>
 
 #include "base/logging.h"
 #include "base/mac/scoped_nsautorelease_pool.h"
@@ skipping 56 matching lines @@
                          printParams.printable_size.width(),
                          printParams.printable_size.height());
 
   printing::Metafile* initial_render_metafile =
       print_preview_context_.metafile();
   scoped_ptr<printing::PreviewMetafile> draft_metafile;
 #if !defined(USE_SKIA)
   if (print_preview_context_.IsModifiable()) {
     draft_metafile.reset(new printing::PreviewMetafile);
     if (!draft_metafile->Init()) {
+      LOG(ERROR) << "Draft PreviewMetafile Init failed";
       return false;
     }
     initial_render_metafile = draft_metafile.get();
   }
 #endif
 
   base::TimeTicks begin_time = base::TimeTicks::Now();
   RenderPage(printParams.page_size, content_area, scale_factor, page_number,
              print_preview_context_.frame(), initial_render_metafile);
   print_preview_context_.RenderedPreviewPage(
@@ skipping 89 matching lines @@
                            print_preview_context_.total_page_count(),
                            scale_factor, page_layout_in_points,
                            *header_footer_info_);
     }
 #endif  // defined(USE_SKIA)
   }
 
   // Done printing. Close the device context to retrieve the compiled metafile.
   metafile->FinishPage();
 }