Mixed Content: Implement strict mode.

Source/core/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 1421 matching lines @@
     SandboxFlags flags = m_forcedSandboxFlags;
     // FIXME: We need a way to propagate sandbox flags to out-of-process frames.
     Frame* parentFrame = m_frame->tree().parent();
     if (parentFrame && parentFrame->isLocalFrame())
         flags |= toLocalFrame(parentFrame)->document()->sandboxFlags();
     if (FrameOwner* frameOwner = m_frame->owner())
         flags |= frameOwner->sandboxFlags();
     return flags;
 }
 
+bool FrameLoader::shouldEnforceStrictMixedContentChecking() const
+{
+    Frame* parentFrame = m_frame->tree().parent();
+    if (!parentFrame)
+        return false;
+
+    // FIXME: We need a way to propagate strict mixed content checking flags to
+    // out-of-process frames. For now, we'll always enforce.
+    if (!parentFrame->isLocalFrame())
+        return true;
+
+    return toLocalFrame(parentFrame)->document()->shouldEnforceStrictMixedContentChecking();
+}
+
 } // namespace blink