[Fetch API] Implement Request.formData and Response.formData.

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

Index: third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp b/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
index bd4a4dfcfa9dc8c685128bd2574425beb071c3de..ffd0ad50f5f5946cf6c2def26461fc6eb1639791 100644
--- a/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
+++ b/third_party/WebKit/Source/modules/fetch/BodyStreamBuffer.cpp
@@ -46,6 +46,11 @@ class BodyStreamBuffer::LoaderClient final
     m_client->didFetchDataLoadedArrayBuffer(arrayBuffer);
   }
 
+  void didFetchDataLoadedFormData(FormData* formData) override {
+    m_buffer->endLoading();
+    m_client->didFetchDataLoadedFormData(formData);
+  }
+
   void didFetchDataLoadedString(const String& string) override {
     m_buffer->endLoading();
     m_client->didFetchDataLoadedString(string);
@@ -281,7 +286,8 @@ void BodyStreamBuffer::closeAndLockAndDisturb() {
 }
 
 void BodyStreamBuffer::close() {
-  controller()->close();
+  if (controller())
+    controller()->close();
   cancelConsumer();
 }