Build content-type string in PasswordCredential::encodeFormData()

third_party/WebKit/Source/modules/fetch/RequestInit.cpp

Index: third_party/WebKit/Source/modules/fetch/RequestInit.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/RequestInit.cpp b/third_party/WebKit/Source/modules/fetch/RequestInit.cpp
index a356d2643f4e1e86015b053a4f1434318855805b..dd14ee8c955bf9f043122129c93286eb20b1e3d0 100644
--- a/third_party/WebKit/Source/modules/fetch/RequestInit.cpp
+++ b/third_party/WebKit/Source/modules/fetch/RequestInit.cpp
@@ -92,11 +92,7 @@ RequestInit::RequestInit(ExecutionContext* context, const Dictionary& options, E
         isCredentialRequest = true;
         PasswordCredential* credential = V8PasswordCredential::toImpl(v8::Local<v8::Object>::Cast(v8Body));
 
-        RefPtr<EncodedFormData> encodedData = credential->encodeFormData();
-        if (encodedData->boundary().isEmpty())
-            contentType = AtomicString("application/x-www-form-urlencoded;charset=UTF-8", AtomicString::ConstructFromLiteral);
-        else
-            contentType = AtomicString("multipart/form-data; boundary=", AtomicString::ConstructFromLiteral) + encodedData->boundary().data();
+        RefPtr<EncodedFormData> encodedData = credential->encodeFormData(contentType);
         body = FetchFormDataConsumerHandle::create(context, encodedData.release());
     } else if (v8Body->IsString()) {
         contentType = "text/plain;charset=UTF-8";