IndexedDB: Fixed support for empty blobs.

storage/browser/blob/blob_data_builder.cc

Index: storage/browser/blob/blob_data_builder.cc
diff --git a/storage/browser/blob/blob_data_builder.cc b/storage/browser/blob/blob_data_builder.cc
index 51946c882f4e8dfec78e38fdfe4966c771695d7e..7c305a2f37719f258f6d1e7099e19a28ea0d9951 100644
--- a/storage/browser/blob/blob_data_builder.cc
+++ b/storage/browser/blob/blob_data_builder.cc
@@ -15,7 +15,8 @@ BlobDataBuilder::~BlobDataBuilder() {
 }
 
 void BlobDataBuilder::AppendData(const char* data, size_t length) {
-  DCHECK(length > 0);
+  if (!length)
+    return;
   scoped_ptr<DataElement> element(new DataElement());
   element->SetToBytes(data, length);
   items_.push_back(new BlobDataItem(element.Pass()));
@@ -25,7 +26,6 @@ void BlobDataBuilder::AppendFile(const base::FilePath& file_path,
                                  uint64_t offset,
                                  uint64_t length,
                                  const base::Time& expected_modification_time) {
-  DCHECK(length > 0);
   scoped_ptr<DataElement> element(new DataElement());
   element->SetToFilePathRange(file_path, offset, length,
                               expected_modification_time);