Move 'frame-src' CSP checks into FrameFetchContext.

third_party/WebKit/Source/core/loader/DocumentLoader.cpp

Index: third_party/WebKit/Source/core/loader/DocumentLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
index 2a76e14272ea498a29abb8fc6931284c241d6a05..56885c71b7c98f4786eda454792f057a7694e12c 100644
--- a/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
@@ -608,6 +608,13 @@ bool DocumentLoader::maybeLoadEmpty()
     return true;
 }
 
+void DocumentLoader::loadUnique()
+{
+    m_request = ResourceRequest(SecurityOrigin::urlWithUniqueSecurityOrigin());
+    m_response = ResourceResponse(m_request.url(), "text/html", 0, nullAtom, String());
+    finishedLoading(monotonicallyIncreasingTime());
+}
+
 void DocumentLoader::startLoadingMainResource()
 {
     timing().markNavigationStart();
@@ -627,8 +634,7 @@ void DocumentLoader::startLoadingMainResource()
     FetchRequest fetchRequest(m_request, FetchInitiatorTypeNames::document, mainResourceLoadOptions);
     m_mainResource = RawResource::fetchMainResource(fetchRequest, fetcher(), m_substituteData);
     if (!m_mainResource) {
-        m_request = ResourceRequest(blankURL());
-        maybeLoadEmpty();
+        loadUnique();
         return;
     }
     // A bunch of headers are set when the underlying ResourceLoader is created, and m_request needs to include those.