[Blob] Fix for resetting reader.

storage/browser/blob/blob_reader.cc

Index: storage/browser/blob/blob_reader.cc
diff --git a/storage/browser/blob/blob_reader.cc b/storage/browser/blob/blob_reader.cc
index 9c6375d5c7d3b2a782f4554068333d8f81bca628..fefcbf2b64320fd110126a5453c1fef9c7668948 100644
--- a/storage/browser/blob/blob_reader.cc
+++ b/storage/browser/blob/blob_reader.cc
@@ -13,7 +13,6 @@
 #include "base/time/time.h"
 #include "base/trace_event/trace_event.h"
 #include "net/base/io_buffer.h"
-#include "net/base/net_errors.h"
 #include "net/disk_cache/disk_cache.h"
 #include "storage/browser/blob/blob_data_handle.h"
 #include "storage/browser/blob/blob_data_snapshot.h"
@@ -43,7 +42,6 @@ BlobReader::BlobReader(
     base::SequencedTaskRunner* file_task_runner)
     : file_stream_provider_(file_stream_provider.Pass()),
       file_task_runner_(file_task_runner),
-      net_error_(net::OK),
       weak_factory_(this) {
   if (blob_handle) {
     blob_data_ = blob_handle->CreateSnapshot().Pass();
@@ -51,7 +49,6 @@ BlobReader::BlobReader(
 }
 
 BlobReader::~BlobReader() {
-  STLDeleteValues(&index_to_reader_);
 }
 
 BlobReader::Status BlobReader::CalculateSize(
@@ -61,7 +58,7 @@ BlobReader::Status BlobReader::CalculateSize(
   if (!blob_data_.get()) {
     return ReportError(net::ERR_FILE_NOT_FOUND);
   }
-
+  dirty_ = true;
   net_error_ = net::OK;
   total_size_ = 0;
   const auto& items = blob_data_->items();
@@ -187,6 +184,7 @@ BlobReader::Status BlobReader::Read(net::IOBuffer* buffer,
 void BlobReader::Kill() {
   DeleteCurrentFileReader();
   weak_factory_.InvalidateWeakPtrs();
+  read_buf_ = nullptr;
 }
 
 bool BlobReader::IsInMemory() const {
@@ -505,14 +503,14 @@ FileStreamReader* BlobReader::GetOrCreateFileReaderAtIndex(size_t index) {
     return nullptr;
   auto it = index_to_reader_.find(index);
   if (it != index_to_reader_.end()) {
-    DCHECK(it->second);
-    return it->second;
+    DCHECK(it->second.get());
+    return it->second.get();
   }
   scoped_ptr<FileStreamReader> reader = CreateFileStreamReader(item, 0);
   FileStreamReader* ret_value = reader.get();
   if (!ret_value)
     return nullptr;
-  index_to_reader_[index] = reader.release();
+  index_to_reader_[index] = std::move(reader);
   return ret_value;
 }
 
@@ -551,19 +549,11 @@ scoped_ptr<FileStreamReader> BlobReader::CreateFileStreamReader(
 
 void BlobReader::SetFileReaderAtIndex(size_t index,
                                       scoped_ptr<FileStreamReader> reader) {
-  auto found = index_to_reader_.find(current_item_index_);
-  if (found != index_to_reader_.end()) {
-    if (found->second) {
-      delete found->second;
-    }
-    if (!reader.get()) {
-      index_to_reader_.erase(found);
-      return;
-    }
-    found->second = reader.release();
-  } else if (reader.get()) {
-    index_to_reader_[current_item_index_] = reader.release();
+  if (!reader.get()) {
+    index_to_reader_.erase(index);
+    return;
   }
+  index_to_reader_[index] = std::move(reader);
 }
 
 }  // namespace storage