Use base::ReadOnlySharedMemoryMapping::GetMemoryAsSpan().

Instead of creating spans from ReadOnlySharedMemoryMappings manually.

Change-Id: I00a1d10eafc58e3eb8e8b6ddb31c27fdcec05643
Reviewed-on: https://chromium-review.googlesource.com/1187742Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585841}

chrome/services/printing/pdf_nup_converter.cc

@@ -27,10 +27,7 @@ std::vector<base::span<const uint8_t>> CreatePdfPagesVector(
 
   for (auto& pdf_page_region : pdf_page_regions) {
     base::ReadOnlySharedMemoryMapping pdf_mapping = pdf_page_region.Map();
-    base::span<const uint8_t> pdf_page =
-        base::make_span(reinterpret_cast<const uint8_t*>(pdf_mapping.memory()),
-                        pdf_mapping.size());
-    pdf_page_span.push_back(pdf_page);
+    pdf_page_span.push_back(pdf_mapping.GetMemoryAsSpan<const uint8_t>());
     pdf_mappings->push_back(std::move(pdf_mapping));
   }
 
@@ -94,9 +91,7 @@ void PdfNupConverter::NupDocumentConvert(
     base::ReadOnlySharedMemoryRegion src_pdf_region,
     NupDocumentConvertCallback callback) {
   base::ReadOnlySharedMemoryMapping pdf_document_mapping = src_pdf_region.Map();
-  base::span<const uint8_t> input_pdf_buffer = base::make_span(
-      static_cast<const uint8_t*>(pdf_document_mapping.memory()),
-      pdf_document_mapping.size());
+  auto input_pdf_buffer = pdf_document_mapping.GetMemoryAsSpan<const uint8_t>();
   void* output_pdf_buffer = nullptr;
   size_t output_pdf_buffer_size = 0;
   if (!chrome_pdf::ConvertPdfDocumentToNupPdf(

chrome/services/printing/pdf_to_emf_converter.cc

@@ -112,8 +112,7 @@ void PdfToEmfConverter::LoadPdf(base::ReadOnlySharedMemoryRegion pdf_region) {
     return;
 
   int page_count = 0;
-  auto pdf_span =
-      base::make_span(static_cast<const uint8_t*>(pdf_mapping_.memory()), size);
+  auto pdf_span = pdf_mapping_.GetMemoryAsSpan<const uint8_t>();
   chrome_pdf::GetPDFDocInfo(pdf_span, &page_count, nullptr);
   total_page_count_ = page_count;
 }
@@ -152,8 +151,7 @@ base::ReadOnlySharedMemoryRegion PdfToEmfConverter::RenderPdfPageToMetafile(
   int offset_y = postscript ? pdf_render_settings_.offsets.y() : 0;
 
   base::ReadOnlySharedMemoryRegion invalid_emf_region;
-  auto pdf_span = base::make_span(
-      static_cast<const uint8_t*>(pdf_mapping_.memory()), pdf_mapping_.size());
+  auto pdf_span = pdf_mapping_.GetMemoryAsSpan<const uint8_t>();
   if (!chrome_pdf::RenderPDFPageToDC(
           pdf_span, page_number, metafile.context(),
           pdf_render_settings_.dpi.width(), pdf_render_settings_.dpi.height(),

chrome/services/printing/pdf_to_pwg_raster_converter.cc

@@ -30,8 +30,7 @@ base::ReadOnlySharedMemoryRegion RenderPdfPagesToPwgRaster(
   if (!pdf_mapping.IsValid())
     return invalid_pwg_region;
 
-  auto pdf_data = base::make_span(
-      static_cast<const uint8_t*>(pdf_mapping.memory()), pdf_mapping.size());
+  auto pdf_data = pdf_mapping.GetMemoryAsSpan<const uint8_t>();
 
   // Get the page count and reserve 64 KB per page in |pwg_data| below.
   static constexpr size_t kEstimatedSizePerPage = 64 * 1024;