Make mixed content checking and CSP aware of RemoteFrames

Source/core/loader/DocumentLoader.cpp

Index: Source/core/loader/DocumentLoader.cpp
diff --git a/Source/core/loader/DocumentLoader.cpp b/Source/core/loader/DocumentLoader.cpp
index 9be513565e329ce4fae54760ae71c2aa0b3ea3a2..eb713e4b2e079d3d263dbaf857484aa1550c5f93 100644
--- a/Source/core/loader/DocumentLoader.cpp
+++ b/Source/core/loader/DocumentLoader.cpp
@@ -371,8 +371,9 @@ void DocumentLoader::willSendRequest(ResourceRequest& newRequest, const Resource
 
     // If this is a sub-frame, check for mixed content blocking against the top frame.
     if (m_frame->tree().parent()) {
-        LocalFrame* top = m_frame->tree().top();
-        if (!top->loader().mixedContentChecker()->canRunInsecureContent(top->document()->securityOrigin(), newRequest.url())) {
+        // FIXME: This does not yet work with out-of-process iframes.
+        Frame* top = m_frame->tree().top();
+        if (top->isLocalFrame() && !toLocalFrame(top)->loader().mixedContentChecker()->canRunInsecureContent(toLocalFrame(top)->document()->securityOrigin(), newRequest.url())) {
             cancelMainResourceLoad(ResourceError::cancelledError(newRequest.url()));
             return;
         }