arc: Use PrintRenderer to render a preview document

When printing from an ARC app, use the provided PrintRenderer to render
a preview document for pint preview. Also, flatten the preview document
received from ARC before displaying it in print preview.

Bug: b:140576300
Test: Print from an ARC app and verify a preview document is displayed
Change-Id: Iae7dcb2184afea51300f2d68edf3af40e55e6f13
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1853324
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Brian White <bcwhite@chromium.org>
Reviewed-by: Yusuke Sato <yusukes@chromium.org>
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Jesse Schettler <jschettler@chromium.org>
Cr-Commit-Position: refs/heads/master@{#713013}

pdf/pdf.cc

@@ -34,6 +34,14 @@ class ScopedSdkInitializer {
 
 }  // namespace
 
+#if defined(OS_CHROMEOS)
+std::vector<uint8_t> CreateFlattenedPdf(
+    base::span<const uint8_t> input_buffer) {
+  ScopedSdkInitializer scoped_sdk_initializer(/*enable_v8=*/false);
+  return PDFEngineExports::Get()->CreateFlattenedPdf(input_buffer);
+}
+#endif  // defined(OS_CHROMEOS)
+
 #if defined(OS_WIN)
 bool RenderPDFPageToDC(base::span<const uint8_t> pdf_buffer,
                        int page_number,

pdf/pdf.h

@@ -27,6 +27,13 @@ class Size;
 
 namespace chrome_pdf {
 
+#if defined(OS_CHROMEOS)
+// Create a flattened PDF document from an existing PDF document.
+// |input_buffer| is the buffer that contains the entire PDF document to be
+// flattened.
+std::vector<uint8_t> CreateFlattenedPdf(base::span<const uint8_t> input_buffer);
+#endif  // defined(OS_CHROMEOS)
+
 #if defined(OS_WIN)
 // Printing modes - type to convert PDF to for printing
 enum PrintingMode {

pdf/pdf_engine.h

@@ -474,6 +474,12 @@ class PDFEngineExports {
 
   static PDFEngineExports* Get();
 
+#if defined(OS_CHROMEOS)
+  // See the definition of CreateFlattenedPdf in pdf.cc for details.
+  virtual std::vector<uint8_t> CreateFlattenedPdf(
+      base::span<const uint8_t> input_buffer) = 0;
+#endif  // defined(OS_CHROMEOS)
+
 #if defined(OS_WIN)
   // See the definition of RenderPDFPageToDC in pdf.cc for details.
   virtual bool RenderPDFPageToDC(base::span<const uint8_t> pdf_buffer,

pdf/pdfium/pdfium_engine_exports.cc

@@ -161,6 +161,16 @@ PDFiumEngineExports::PDFiumEngineExports() {}
 
 PDFiumEngineExports::~PDFiumEngineExports() {}
 
+#if defined(OS_CHROMEOS)
+std::vector<uint8_t> PDFiumEngineExports::CreateFlattenedPdf(
+    base::span<const uint8_t> input_buffer) {
+  ScopedFPDFDocument doc = LoadPdfData(input_buffer);
+  if (!doc)
+    return std::vector<uint8_t>();
+  return PDFiumPrint::CreateFlattenedPdf(std::move(doc));
+}
+#endif  // defined(OS_CHROMEOS)
+
 #if defined(OS_WIN)
 bool PDFiumEngineExports::RenderPDFPageToDC(
     base::span<const uint8_t> pdf_buffer,

pdf/pdfium/pdfium_engine_exports.h

@@ -19,6 +19,10 @@ class PDFiumEngineExports : public PDFEngineExports {
   ~PDFiumEngineExports() override;
 
 // PDFEngineExports:
+#if defined(OS_CHROMEOS)
+  std::vector<uint8_t> CreateFlattenedPdf(
+      base::span<const uint8_t> input_buffer) override;
+#endif  // defined(OS_CHROMEOS)
 #if defined(OS_WIN)
   bool RenderPDFPageToDC(base::span<const uint8_t> pdf_buffer,
                          int page_number,

pdf/pdfium/pdfium_print.cc

@@ -254,12 +254,34 @@ std::string GetPageRangeStringFromRange(
   return page_number_str;
 }
 
+bool FlattenPrintData(FPDF_DOCUMENT doc) {
+  DCHECK(doc);
+
+  int page_count = FPDF_GetPageCount(doc);
+  for (int i = 0; i < page_count; ++i) {
+    ScopedFPDFPage page(FPDF_LoadPage(doc, i));
+    DCHECK(page);
+    if (FPDFPage_Flatten(page.get(), FLAT_PRINT) == FLATTEN_FAIL)
+      return false;
+  }
+  return true;
+}
+
 }  // namespace
 
 PDFiumPrint::PDFiumPrint(PDFiumEngine* engine) : engine_(engine) {}
 
 PDFiumPrint::~PDFiumPrint() = default;
 
+#if defined(OS_CHROMEOS)
+// static
+std::vector<uint8_t> PDFiumPrint::CreateFlattenedPdf(ScopedFPDFDocument doc) {
+  if (!FlattenPrintData(doc.get()))
+    return std::vector<uint8_t>();
+  return ConvertDocToBuffer(std::move(doc));
+}
+#endif  // defined(OS_CHROMEOS)
+
 // static
 std::vector<uint32_t> PDFiumPrint::GetPageNumbersFromPrintPageNumberRange(
     const PP_PrintPageNumberRange_Dev* page_ranges,
@@ -477,17 +499,4 @@ ScopedFPDFDocument PDFiumPrint::CreateSinglePageRasterPdf(
   return temp_doc;
 }
 
-bool PDFiumPrint::FlattenPrintData(FPDF_DOCUMENT doc) const {
-  DCHECK(doc);
-
-  int page_count = FPDF_GetPageCount(doc);
-  for (int i = 0; i < page_count; ++i) {
-    ScopedFPDFPage page(FPDF_LoadPage(doc, i));
-    DCHECK(page);
-    if (FPDFPage_Flatten(page.get(), FLAT_PRINT) == FLATTEN_FAIL)
-      return false;
-  }
-  return true;
-}
-
 }  // namespace chrome_pdf

pdf/pdfium/pdfium_print.h

@@ -8,6 +8,7 @@
 #include <vector>
 
 #include "base/macros.h"
+#include "build/build_config.h"
 #include "third_party/pdfium/public/cpp/fpdf_scopers.h"
 #include "third_party/pdfium/public/fpdfview.h"
 
@@ -29,6 +30,13 @@ class PDFiumPrint {
   explicit PDFiumPrint(PDFiumEngine* engine);
   ~PDFiumPrint();
 
+#if defined(OS_CHROMEOS)
+  // Flattens the |doc|.
+  // On success, returns the flattened version of |doc| as a vector.
+  // On failure, returns an empty vector.
+  static std::vector<uint8_t> CreateFlattenedPdf(ScopedFPDFDocument doc);
+#endif  // defined(OS_CHROMEOS)
+
   static std::vector<uint32_t> GetPageNumbersFromPrintPageNumberRange(
       const PP_PrintPageNumberRange_Dev* page_ranges,
       uint32_t page_range_count);
@@ -77,8 +85,6 @@ class PDFiumPrint {
       FPDF_PAGE page_to_print,
       const PP_PrintSettings_Dev& print_settings);
 
-  bool FlattenPrintData(FPDF_DOCUMENT doc) const;
-
   PDFiumEngine* const engine_;
 
   DISALLOW_COPY_AND_ASSIGN(PDFiumPrint);