Introduce url_list to the Response scheme of CacheStorage.

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

Index: third_party/WebKit/Source/modules/fetch/FetchResponseData.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/FetchResponseData.cpp b/third_party/WebKit/Source/modules/fetch/FetchResponseData.cpp
index d835e25e66235919548132294a8b438e201df6c9..34da2108bd242314bbb247acb520eebb5da2a3b5 100644
--- a/third_party/WebKit/Source/modules/fetch/FetchResponseData.cpp
+++ b/third_party/WebKit/Source/modules/fetch/FetchResponseData.cpp
@@ -81,7 +81,7 @@ FetchResponseData* FetchResponseData::createBasicFilteredResponse() const {
   // name is `Set-Cookie` or `Set-Cookie2`."
   FetchResponseData* response =
       new FetchResponseData(BasicType, m_status, m_statusMessage);
-  response->m_url = m_url;
+  response->setURLList(m_urlList);
   for (size_t i = 0; i < m_headerList->size(); ++i) {
     const FetchHeaderList::Header* header = m_headerList->list()[i].get();
     if (FetchUtils::isForbiddenResponseHeaderName(header->first))
@@ -117,7 +117,7 @@ FetchResponseData* FetchResponseData::createCORSFilteredResponse(
   // list."
   FetchResponseData* response =
       new FetchResponseData(CORSType, m_status, m_statusMessage);
-  response->m_url = m_url;
+  response->setURLList(m_urlList);
   for (size_t i = 0; i < m_headerList->size(); ++i) {
     const FetchHeaderList::Header* header = m_headerList->list()[i].get();
     const String& name = header->first;
@@ -159,11 +159,19 @@ FetchResponseData* FetchResponseData::createOpaqueRedirectFilteredResponse()
   // https://fetch.spec.whatwg.org/#concept-filtered-response-opaque-redirect
   FetchResponseData* response =
       new FetchResponseData(OpaqueRedirectType, 0, "");
-  response->m_url = m_url;
+  response->setURLList(m_urlList);
   response->m_internalResponse = const_cast<FetchResponseData*>(this);
   return response;
 }
 
+const KURL* FetchResponseData::url() const {
+  // "A response has an associated url. It is a pointer to the last response URL
+  // in response’s url list and null if response’s url list is the empty list."
+  if (m_urlList.isEmpty())
+    return nullptr;
+  return &m_urlList.back();
+}
+
 String FetchResponseData::mimeType() const {
   return m_mimeType;
 }
@@ -182,6 +190,10 @@ String FetchResponseData::internalMIMEType() const {
   return m_mimeType;
 }
 
+void FetchResponseData::setURLList(const Vector<KURL>& urlList) {
+  m_urlList = urlList;
+}
+
 FetchResponseData* FetchResponseData::clone(ScriptState* scriptState) {
   FetchResponseData* newResponse = create();
   newResponse->m_type = m_type;
@@ -189,7 +201,7 @@ FetchResponseData* FetchResponseData::clone(ScriptState* scriptState) {
     newResponse->m_terminationReason = wrapUnique(new TerminationReason);
     *newResponse->m_terminationReason = *m_terminationReason;
   }
-  newResponse->m_url = m_url;
+  newResponse->setURLList(m_urlList);
   newResponse->m_status = m_status;
   newResponse->m_statusMessage = m_statusMessage;
   newResponse->m_headerList = m_headerList->clone();
@@ -243,8 +255,7 @@ void FetchResponseData::populateWebServiceWorkerResponse(
         headerSetToWebVector(m_corsExposedHeaderNames));
     return;
   }
-
-  response.setURL(url());
+  response.setURLList(m_urlList);
   response.setStatus(status());
   response.setStatusText(statusMessage());
   response.setResponseType(fetchTypeToWebType(m_type));