Instead of ArrayBuffer, pass blob with printerProvider.onPrintRequested

content/browser/fileapi/chrome_blob_storage_context.cc

Index: content/browser/fileapi/chrome_blob_storage_context.cc
diff --git a/content/browser/fileapi/chrome_blob_storage_context.cc b/content/browser/fileapi/chrome_blob_storage_context.cc
index f8753b5ea77e521d8f0c4fc24d517ee965bfdd6c..1f8acc8f7a6332030b38c0da0934157ca8fe9d3e 100644
--- a/content/browser/fileapi/chrome_blob_storage_context.cc
+++ b/content/browser/fileapi/chrome_blob_storage_context.cc
@@ -82,6 +82,27 @@ scoped_ptr<BlobHandle> ChromeBlobStorageContext::CreateMemoryBackedBlob(
   return blob_handle.Pass();
 }
 
+scoped_ptr<BlobHandle> ChromeBlobStorageContext::CreateFileBackedBlob(
+    const base::FilePath& path,
+    int64_t offset,
+    int64_t size,
+    const base::Time& expected_modification_time) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  std::string uuid(base::GenerateGUID());
+  storage::BlobDataBuilder blob_data_builder(uuid);
+  blob_data_builder.AppendFile(path, offset, size, expected_modification_time);
+
+  scoped_ptr<storage::BlobDataHandle> blob_data_handle =
+      context_->AddFinishedBlob(&blob_data_builder);
+  if (!blob_data_handle)
+    return scoped_ptr<BlobHandle>();
+
+  scoped_ptr<BlobHandle> blob_handle(
+      new BlobHandleImpl(blob_data_handle.Pass()));
+  return blob_handle.Pass();
+}
+
 ChromeBlobStorageContext::~ChromeBlobStorageContext() {}
 
 void ChromeBlobStorageContext::DeleteOnCorrectThread() const {