Instead of ArrayBuffer, pass blob with printerProvider.onPrintRequested

extensions/browser/api/printer_provider_internal/printer_provider_internal_api.cc

 // Copyright 2015 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 "extensions/browser/api/printer_provider_internal/printer_provider_internal_api.h"
 
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/guid.h"
 #include "base/lazy_instance.h"
+#include "base/location.h"
+#include "base/memory/ref_counted_memory.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/values.h"
+#include "content/public/browser/blob_handle.h"
+#include "content/public/browser/browser_context.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/web_contents.h"
+#include "extensions/browser/api/printer_provider/printer_provider_api.h"
+#include "extensions/browser/api/printer_provider/printer_provider_api_factory.h"
+#include "extensions/browser/api/printer_provider/printer_provider_print_job.h"
+#include "extensions/browser/blob_holder.h"
 #include "extensions/common/api/printer_provider.h"
 #include "extensions/common/api/printer_provider_internal.h"
 
 namespace internal_api = extensions::core_api::printer_provider_internal;
 
 namespace extensions {
 
 namespace {
 
 static base::LazyInstance<
@@ skipping 120 matching lines @@
   } else {
     PrinterProviderInternalAPI::GetFactoryInstance()
         ->Get(browser_context())
         ->NotifyGetPrintersResult(
             extension(), params->request_id,
             PrinterProviderInternalAPIObserver::PrinterInfoVector());
   }
   return RespondNow(NoArguments());
 }
 
+PrinterProviderInternalGetPrintDataFunction::
+    PrinterProviderInternalGetPrintDataFunction() {
+}
+
+PrinterProviderInternalGetPrintDataFunction::
+    ~PrinterProviderInternalGetPrintDataFunction() {
+}
+
+ExtensionFunction::ResponseAction
+PrinterProviderInternalGetPrintDataFunction::Run() {
+  scoped_ptr<internal_api::GetPrintData::Params> params(
+      internal_api::GetPrintData::Params::Create(*args_));
+  EXTENSION_FUNCTION_VALIDATE(params.get());
+
+  const PrinterProviderPrintJob* job =
+      PrinterProviderAPIFactory::GetInstance()
+          ->GetForBrowserContext(browser_context())
+          ->GetPrintJob(extension(), params->request_id);
+  if (!job)
+    return RespondNow(Error("Print request not found."));
+
+  if (job->document_bytes.get()) {
+    // |job->document_bytes| are passed to the callback to make sure the ref
+    // counted memory does not go away before the memory backed blob is created.
+    content::BrowserContext::CreateMemoryBackedBlob(
+        browser_context(), job->document_bytes->front_as<char>(),
+        job->document_bytes->size(),
+        base::Bind(&PrinterProviderInternalGetPrintDataFunction::OnBlob, this,
+                   job->content_type, job->document_bytes->size(),
+                   job->document_bytes));
+  } else if (!job->document_path.empty()) {
+    content::BrowserContext::CreateFileBackedBlob(
+        browser_context(), job->document_path, 0 /* offset */,
+        job->file_info.size, job->file_info.last_modified,
+        base::Bind(&PrinterProviderInternalGetPrintDataFunction::OnBlob, this,
+                   job->content_type, job->file_info.size,
+                   scoped_refptr<base::RefCountedMemory>()));
+  } else {
+    return RespondNow(Error("Job data not set"));
+  }
+  return RespondLater();
+}
+
+void PrinterProviderInternalGetPrintDataFunction::OnBlob(
+    const std::string& type,
+    int size,
+    const scoped_refptr<base::RefCountedMemory>& data,
+    scoped_ptr<content::BlobHandle> blob) {
+  if (!blob) {
+    SetError("Unable to create the blob.");
+    SendResponse(false);
+    return;
+  }
+
+  internal_api::BlobInfo info;
+  info.blob_uuid = blob->GetUUID();
+  info.type = type;
+  info.size = size;
+
+  std::vector<std::string> uuids;
+  uuids.push_back(blob->GetUUID());
+
+  content::WebContents* contents =
+      content::WebContents::FromRenderViewHost(render_view_host());
+  extensions::BlobHolder* holder =
+      extensions::BlobHolder::FromRenderProcessHost(
+          contents->GetRenderProcessHost());
+  holder->HoldBlobReference(blob.Pass());
+
+  results_ = internal_api::GetPrintData::Results::Create(info);
+  SetTransferredBlobUUIDs(uuids);
+  SendResponse(true);
+}
+
 }  // namespace extensions