PDF Printing: embed browser user agent string in PDF metadata.

printing/pdf_metafile_skia.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 "printing/pdf_metafile_skia.h"
 
 #include "base/containers/hash_tables.h"
 #include "base/files/file_util.h"
 #include "base/metrics/histogram.h"
 #include "base/numerics/safe_conversions.h"
 #include "base/posix/eintr_wrapper.h"
 #include "base/time/time.h"
+#include "printing/print_settings.h"
 #include "skia/ext/refptr.h"
 #include "third_party/skia/include/core/SkData.h"
 #include "third_party/skia/include/core/SkDocument.h"
 #include "third_party/skia/include/core/SkPictureRecorder.h"
 #include "third_party/skia/include/core/SkRect.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
 #include "third_party/skia/include/core/SkScalar.h"
 #include "third_party/skia/include/core/SkSize.h"
 #include "third_party/skia/include/core/SkStream.h"
 #include "ui/gfx/geometry/point.h"
@@ skipping 133 matching lines @@
       skia::AdoptRef(SkDocument::CreatePDF(&pdf_stream));
   for (const auto& page : data_->pages_) {
     SkCanvas* canvas = pdf_doc->beginPage(
         page.page_size_.width(), page.page_size_.height(), &page.content_area_);
     // No need to save/restore, since this canvas is not reused after endPage()
     canvas->scale(page.scale_factor_, page.scale_factor_);
     canvas->drawPicture(page.content_.get());
     pdf_doc->endPage();
   }
   SkTArray<SkDocument::Attribute> info;
-  info.emplace_back(SkString("Creator"), SkString("Chromium"));
+  const std::string& user_agent = GetAgent();
+  info.emplace_back(SkString("Creator"),
+                    user_agent.empty() ? SkString("Chromium")
+                    : SkString(user_agent.c_str(), user_agent.size()));

[Lei Zhang, 2015/11/05 22:24:09]

Can we do this in some way as suggested by the style guide?
https://www.chromium.org/developers/coding-style#Code_Formatting

[hal.canary, 2015/11/05 22:34:53]

done

   SkTime::DateTime now = TimeToSkTime(base::Time::Now());
   pdf_doc->setMetadata(info, &now, &now);
   if (!pdf_doc->close())
     return false;
 
   data_->pdf_data_.reset(pdf_stream.detachAsStream());
   return true;
 }
 
 uint32_t PdfMetafileSkia::GetDataSize() const {
@@ skipping 124 matching lines @@
 
   metafile->data_->pages_.push_back(page);
 
   if (!metafile->FinishDocument())  // Generate PDF.
     metafile.reset();
 
   return metafile.Pass();
 }
 
 }  // namespace printing