Convert //chrome/browser/extensions from scoped_ptr to std::unique_ptr

chrome/browser/extensions/blob_reader.cc

Index: chrome/browser/extensions/blob_reader.cc
diff --git a/chrome/browser/extensions/blob_reader.cc b/chrome/browser/extensions/blob_reader.cc
index 2427c3fb0171d51ae16c6926c531c786122ca960..eca646e80ebfdc64eaccf22295ce1a8e5ccd684d 100644
--- a/chrome/browser/extensions/blob_reader.cc
+++ b/chrome/browser/extensions/blob_reader.cc
@@ -60,7 +60,7 @@ void BlobReader::Start() {
 // Overridden from net::URLFetcherDelegate.
 void BlobReader::OnURLFetchComplete(const net::URLFetcher* source) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
-  scoped_ptr<std::string> response(new std::string);
+  std::unique_ptr<std::string> response(new std::string);
   int64_t first = 0, last = 0, length = 0;
   source->GetResponseAsString(response.get());
   source->GetResponseHeaders()->GetContentRange(&first, &last, &length);