--- a/dom/base/nsContentPolicy.cpp
+++ b/dom/base/nsContentPolicy.cpp
@@ -8,16 +8,17 @@
  * Implementation of the "@mozilla.org/layout/content-policy;1" contract.
  */
 
 #include "mozilla/Logging.h"
 
 #include "nsISupports.h"
 #include "nsXPCOM.h"
 #include "nsContentPolicyUtils.h"
+#include "mozilla/dom/nsCSPService.h"
 #include "nsContentPolicy.h"
 #include "nsIURI.h"
 #include "nsIDocShell.h"
 #include "nsIDOMElement.h"
 #include "nsIDOMNode.h"
 #include "nsIDOMWindow.h"
 #include "nsIContent.h"
 #include "nsILoadContext.h"
@@ -118,19 +119,25 @@ nsContentPolicy::CheckPolicy(CPMethod   
     }
 
     nsContentPolicyType externalType =
         nsContentUtils::InternalContentPolicyTypeToExternal(contentType);
 
     nsContentPolicyType externalTypeOrScript =
         nsContentUtils::InternalContentPolicyTypeToExternalOrScript(contentType);
 
+    nsContentPolicyType externalTypeOrPreload =
+       nsContentUtils::InternalContentPolicyTypeToExternalOrPreload(contentType);
+
     nsCOMPtr<nsIContentPolicy> mixedContentBlocker =
         do_GetService(NS_MIXEDCONTENTBLOCKER_CONTRACTID);
 
+    nsCOMPtr<nsIContentPolicy> cspService =
+      do_GetService(CSPSERVICE_CONTRACTID);
+
     /* 
      * Enumerate mPolicies and ask each of them, taking the logical AND of
      * their permissions.
      */
     nsresult rv;
     nsCOMArray<nsIContentPolicy> entries;
     mPolicies.GetEntries(entries);
     int32_t count = entries.Count();
@@ -139,16 +146,25 @@ nsContentPolicy::CheckPolicy(CPMethod   
         // Send the internal content policy type to the mixed content blocker
         // which needs to know about TYPE_INTERNAL_WORKER,
         // TYPE_INTERNAL_SHARED_WORKER and TYPE_INTERNAL_SERVICE_WORKER.
         bool isMixedContentBlocker = mixedContentBlocker == entries[i];
         nsContentPolicyType type = externalType;
         if (isMixedContentBlocker) {
             type = externalTypeOrScript;
         }
+        // Send the internal content policy type for CSP which needs to
+        // know about preloads, in particular:
+        // * TYPE_INTERNAL_SCRIPT_PRELOAD
+        // * TYPE_INTERNAL_IMAGE_PRELOAD
+        // * TYPE_INTERNAL_STYLESHEET_PRELOAD
+        bool isCSP = cspService == entries[i];
+        if (isCSP) {
+          type = externalTypeOrPreload;
+        }
         rv = (entries[i]->*policyMethod)(type, contentLocation,
                                          requestingLocation, requestingContext,
                                          mimeType, extra, requestPrincipal,
                                          decision);
 
         if (NS_SUCCEEDED(rv) && NS_CP_REJECTED(*decision)) {
             /* policy says no, no point continuing to check */
             return NS_OK;

--- a/dom/base/nsContentPolicyUtils.h
+++ b/dom/base/nsContentPolicyUtils.h
@@ -87,51 +87,56 @@ NS_CP_ResponseName(int16_t response)
  *
  * @param contentType the content type code
  * @return the name of the given content type code
  */
 inline const char *
 NS_CP_ContentTypeName(uint32_t contentType)
 {
   switch (contentType) {
-    CASE_RETURN( TYPE_OTHER                   );
-    CASE_RETURN( TYPE_SCRIPT                  );
-    CASE_RETURN( TYPE_IMAGE                   );
-    CASE_RETURN( TYPE_STYLESHEET              );
-    CASE_RETURN( TYPE_OBJECT                  );
-    CASE_RETURN( TYPE_DOCUMENT                );
-    CASE_RETURN( TYPE_SUBDOCUMENT             );
-    CASE_RETURN( TYPE_REFRESH                 );
-    CASE_RETURN( TYPE_XBL                     );
-    CASE_RETURN( TYPE_PING                    );
-    CASE_RETURN( TYPE_XMLHTTPREQUEST          );
-    CASE_RETURN( TYPE_OBJECT_SUBREQUEST       );
-    CASE_RETURN( TYPE_DTD                     );
-    CASE_RETURN( TYPE_FONT                    );
-    CASE_RETURN( TYPE_MEDIA                   );
-    CASE_RETURN( TYPE_WEBSOCKET               );
-    CASE_RETURN( TYPE_CSP_REPORT              );
-    CASE_RETURN( TYPE_XSLT                    );
-    CASE_RETURN( TYPE_BEACON                  );
-    CASE_RETURN( TYPE_FETCH                   );
-    CASE_RETURN( TYPE_IMAGESET                );
-    CASE_RETURN( TYPE_WEB_MANIFEST            );
-    CASE_RETURN( TYPE_INTERNAL_SCRIPT         );
-    CASE_RETURN( TYPE_INTERNAL_WORKER         );
-    CASE_RETURN( TYPE_INTERNAL_SHARED_WORKER  );
-    CASE_RETURN( TYPE_INTERNAL_EMBED          );
-    CASE_RETURN( TYPE_INTERNAL_OBJECT         );
-    CASE_RETURN( TYPE_INTERNAL_FRAME          );
-    CASE_RETURN( TYPE_INTERNAL_IFRAME         );
-    CASE_RETURN( TYPE_INTERNAL_AUDIO          );
-    CASE_RETURN( TYPE_INTERNAL_VIDEO          );
-    CASE_RETURN( TYPE_INTERNAL_TRACK          );
-    CASE_RETURN( TYPE_INTERNAL_XMLHTTPREQUEST );
-    CASE_RETURN( TYPE_INTERNAL_EVENTSOURCE    );
-    CASE_RETURN( TYPE_INTERNAL_SERVICE_WORKER );
+    CASE_RETURN( TYPE_OTHER                       );
+    CASE_RETURN( TYPE_SCRIPT                      );
+    CASE_RETURN( TYPE_IMAGE                       );
+    CASE_RETURN( TYPE_STYLESHEET                  );
+    CASE_RETURN( TYPE_OBJECT                      );
+    CASE_RETURN( TYPE_DOCUMENT                    );
+    CASE_RETURN( TYPE_SUBDOCUMENT                 );
+    CASE_RETURN( TYPE_REFRESH                     );
+    CASE_RETURN( TYPE_XBL                         );
+    CASE_RETURN( TYPE_PING                        );
+    CASE_RETURN( TYPE_XMLHTTPREQUEST              );
+    CASE_RETURN( TYPE_OBJECT_SUBREQUEST           );
+    CASE_RETURN( TYPE_DTD                         );
+    CASE_RETURN( TYPE_FONT                        );
+    CASE_RETURN( TYPE_MEDIA                       );
+    CASE_RETURN( TYPE_WEBSOCKET                   );
+    CASE_RETURN( TYPE_CSP_REPORT                  );
+    CASE_RETURN( TYPE_XSLT                        );
+    CASE_RETURN( TYPE_BEACON                      );
+    CASE_RETURN( TYPE_FETCH                       );
+    CASE_RETURN( TYPE_IMAGESET                    );
+    CASE_RETURN( TYPE_WEB_MANIFEST                );
+    CASE_RETURN( TYPE_INTERNAL_SCRIPT             );
+    CASE_RETURN( TYPE_INTERNAL_WORKER             );
+    CASE_RETURN( TYPE_INTERNAL_SHARED_WORKER      );
+    CASE_RETURN( TYPE_INTERNAL_EMBED              );
+    CASE_RETURN( TYPE_INTERNAL_OBJECT             );
+    CASE_RETURN( TYPE_INTERNAL_FRAME              );
+    CASE_RETURN( TYPE_INTERNAL_IFRAME             );
+    CASE_RETURN( TYPE_INTERNAL_AUDIO              );
+    CASE_RETURN( TYPE_INTERNAL_VIDEO              );
+    CASE_RETURN( TYPE_INTERNAL_TRACK              );
+    CASE_RETURN( TYPE_INTERNAL_XMLHTTPREQUEST     );
+    CASE_RETURN( TYPE_INTERNAL_EVENTSOURCE        );
+    CASE_RETURN( TYPE_INTERNAL_SERVICE_WORKER     );
+    CASE_RETURN( TYPE_INTERNAL_SCRIPT_PRELOAD     );
+    CASE_RETURN( TYPE_INTERNAL_IMAGE              );
+    CASE_RETURN( TYPE_INTERNAL_IMAGE_PRELOAD      );
+    CASE_RETURN( TYPE_INTERNAL_STYLESHEET         );
+    CASE_RETURN( TYPE_INTERNAL_STYLESHEET_PRELOAD );
    default:
     return "<Unknown Type>";
   }
 }
 
 #undef CASE_RETURN
 
 /* Passes on parameters from its "caller"'s context. */

--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -7954,16 +7954,17 @@ nsContentUtils::GetWindowRoot(nsIDocumen
 }
 
 /* static */
 nsContentPolicyType
 nsContentUtils::InternalContentPolicyTypeToExternal(nsContentPolicyType aType)
 {
   switch (aType) {
   case nsIContentPolicy::TYPE_INTERNAL_SCRIPT:
+  case nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD:
   case nsIContentPolicy::TYPE_INTERNAL_WORKER:
   case nsIContentPolicy::TYPE_INTERNAL_SHARED_WORKER:
   case nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER:
     return nsIContentPolicy::TYPE_SCRIPT;
 
   case nsIContentPolicy::TYPE_INTERNAL_EMBED:
   case nsIContentPolicy::TYPE_INTERNAL_OBJECT:
     return nsIContentPolicy::TYPE_OBJECT;
@@ -7976,16 +7977,24 @@ nsContentUtils::InternalContentPolicyTyp
   case nsIContentPolicy::TYPE_INTERNAL_VIDEO:
   case nsIContentPolicy::TYPE_INTERNAL_TRACK:
     return nsIContentPolicy::TYPE_MEDIA;
 
   case nsIContentPolicy::TYPE_INTERNAL_XMLHTTPREQUEST:
   case nsIContentPolicy::TYPE_INTERNAL_EVENTSOURCE:
     return nsIContentPolicy::TYPE_XMLHTTPREQUEST;
 
+  case nsIContentPolicy::TYPE_INTERNAL_IMAGE:
+  case nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD:
+    return nsIContentPolicy::TYPE_IMAGE;
+
+  case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET:
+  case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD:
+    return nsIContentPolicy::TYPE_STYLESHEET;
+
   default:
     return aType;
   }
 }
 
 /* static */
 nsContentPolicyType
 nsContentUtils::InternalContentPolicyTypeToExternalOrScript(nsContentPolicyType aType)
@@ -7997,16 +8006,27 @@ nsContentUtils::InternalContentPolicyTyp
   case nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER:
     return aType;
 
   default:
     return InternalContentPolicyTypeToExternal(aType);
   }
 }
 
+/* static */
+nsContentPolicyType
+nsContentUtils::InternalContentPolicyTypeToExternalOrPreload(nsContentPolicyType aType)
+{
+  if (aType == nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD ||
+      aType == nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD ||
+      aType == nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD) {
+    return aType;
+  }
+  return InternalContentPolicyTypeToExternal(aType);
+}
 
 nsresult
 nsContentUtils::SetFetchReferrerURIWithPolicy(nsIPrincipal* aPrincipal,
                                               nsIDocument* aDoc,
                                               nsIHttpChannel* aChannel)
 {
   NS_ENSURE_ARG_POINTER(aPrincipal);
   NS_ENSURE_ARG_POINTER(aChannel);

--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -961,16 +961,26 @@ public:
    *   * TYPE_INTERNAL_SERVICE_WORKER
    *
    *
    * Note: DO NOT call this function unless you know what you're doing!
    */
   static nsContentPolicyType InternalContentPolicyTypeToExternalOrScript(nsContentPolicyType aType);
 
   /**
+   * Map internal content policy types to external ones or preload types:
+   *   * TYPE_INTERNAL_SCRIPT_PRELOAD
+   *   * TYPE_INTERNAL_IMAGE_PRELOAD
+   *   * TYPE_INTERNAL_STYLESHEET_PRELOAD
+   *
+   * Note: DO NOT call this function unless you know what you're doing!
+   */
+  static nsContentPolicyType InternalContentPolicyTypeToExternalOrPreload(nsContentPolicyType aType);
+
+  /**
    * Quick helper to determine whether there are any mutation listeners
    * of a given type that apply to this content or any of its ancestors.
    * The method has the side effect to call document's MayDispatchMutationEvent
    * using aTargetForSubtreeModified as the parameter.
    *
    * @param aNode  The node to search for listeners
    * @param aType  The type of listener (NS_EVENT_BITS_MUTATION_*)
    * @param aTargetForSubtreeModified The node which is the target of the

--- a/dom/base/nsIContentPolicy.idl
+++ b/dom/base/nsIContentPolicy.idl
@@ -15,17 +15,17 @@ interface nsIPrincipal;
  * Interface for content policy mechanism.  Implementations of this
  * interface can be used to control loading of various types of out-of-line
  * content, or processing of certain types of in-line content.
  *
  * WARNING: do not block the caller from shouldLoad or shouldProcess (e.g.,
  * by launching a dialog to prompt the user for something).
  */
 
-[scriptable,uuid(ce321216-c404-40a7-a711-d80454ec6b76)]
+[scriptable,uuid(caad4f1f-d047-46ac-ae9d-dc598e4fb91b)]
 interface nsIContentPolicy : nsIContentPolicyBase
 {
   /**
    * Should the resource at this location be loaded?
    * ShouldLoad will be called before loading the resource at aContentLocation
    * to determine whether to start the load at all.
    *
    * @param aContentType      the type of content being tested. This will be one

--- a/dom/base/nsIContentPolicyBase.idl
+++ b/dom/base/nsIContentPolicyBase.idl
@@ -19,17 +19,17 @@ typedef unsigned long nsContentPolicyTyp
  * Interface for content policy mechanism.  Implementations of this
  * interface can be used to control loading of various types of out-of-line
  * content, or processing of certain types of in-line content.
  *
  * WARNING: do not block the caller from shouldLoad or shouldProcess (e.g.,
  * by launching a dialog to prompt the user for something).
  */
 
-[scriptable,uuid(8527ae0d-0c43-4413-bc46-85c0bcb66876)]
+[scriptable,uuid(17418187-d86f-48dd-92d1-238838df0a4e)]
 interface nsIContentPolicyBase : nsISupports
 {
   /**
    * Indicates a unset or bogus policy type.
    */
   const nsContentPolicyType TYPE_INVALID = 0;
 
   /**
@@ -275,16 +275,57 @@ interface nsIContentPolicyBase : nsISupp
    * Indicates an internal constant for scripts loaded through a service
    * worker.
    *
    * This will be mapped to TYPE_SCRIPT before being passed to content policy
    * implementations.
    */
   const nsContentPolicyType TYPE_INTERNAL_SERVICE_WORKER = 35;
 
+  /**
+   * Indicates an internal constant for *preloaded* scripts
+   * loaded through script elements.
+   *
+   * This will be mapped to TYPE_SCRIPT before being passed
+   * to content policy implementations.
+   */
+  const nsContentPolicyType TYPE_INTERNAL_SCRIPT_PRELOAD = 36;
+
+  /**
+   * Indicates an internal constant for normal images.
+   *
+   * This will be mapped to TYPE_IMAGE before being passed
+   * to content policy implementations.
+   */
+  const nsContentPolicyType TYPE_INTERNAL_IMAGE = 37;
+
+  /**
+   * Indicates an internal constant for *preloaded* images.
+   *
+   * This will be mapped to TYPE_IMAGE before being passed
+   * to content policy implementations.
+   */
+  const nsContentPolicyType TYPE_INTERNAL_IMAGE_PRELOAD = 38;
+
+  /**
+   * Indicates an internal constant for normal stylesheets.
+   *
+   * This will be mapped to TYPE_STYLESHEET before being passed
+   * to content policy implementations.
+   */
+  const nsContentPolicyType TYPE_INTERNAL_STYLESHEET = 39;
+
+  /**
+   * Indicates an internal constant for *preloaded* stylesheets.
+   *
+   * This will be mapped to TYPE_STYLESHEET before being passed
+   * to content policy implementations.
+   */
+  const nsContentPolicyType TYPE_INTERNAL_STYLESHEET_PRELOAD = 40;
+
   /* When adding new content types, please update nsContentBlocker,
    * NS_CP_ContentTypeName, nsCSPContext, all nsIContentPolicy
    * implementations, the static_assert in dom/cache/DBSchema.cpp,
    * and other things that are not listed here that are related to
    * nsIContentPolicy. */
 
   //////////////////////////////////////////////////////////////////////
 

--- a/dom/cache/DBSchema.cpp
+++ b/dom/cache/DBSchema.cpp
@@ -270,17 +270,22 @@ static_assert(nsIContentPolicy::TYPE_INV
               nsIContentPolicy::TYPE_INTERNAL_OBJECT == 27 &&
               nsIContentPolicy::TYPE_INTERNAL_FRAME == 28 &&
               nsIContentPolicy::TYPE_INTERNAL_IFRAME == 29 &&
               nsIContentPolicy::TYPE_INTERNAL_AUDIO == 30 &&
               nsIContentPolicy::TYPE_INTERNAL_VIDEO == 31 &&
               nsIContentPolicy::TYPE_INTERNAL_TRACK == 32 &&
               nsIContentPolicy::TYPE_INTERNAL_XMLHTTPREQUEST == 33 &&
               nsIContentPolicy::TYPE_INTERNAL_EVENTSOURCE == 34 &&
-              nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER == 35,
+              nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER == 35 &&
+              nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD == 36 &&
+              nsIContentPolicy::TYPE_INTERNAL_IMAGE == 37 &&
+              nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD == 38 &&
+              nsIContentPolicy::TYPE_INTERNAL_STYLESHEET == 39 &&
+              nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD == 40,
               "nsContentPolicyType values are as expected");
 
 namespace {
 
 typedef int32_t EntryId;
 
 struct IdCount
 {

--- a/dom/fetch/InternalRequest.cpp
+++ b/dom/fetch/InternalRequest.cpp
@@ -111,29 +111,32 @@ RequestContext
 InternalRequest::MapContentPolicyTypeToRequestContext(nsContentPolicyType aContentPolicyType)
 {
   RequestContext context = RequestContext::Internal;
   switch (aContentPolicyType) {
   case nsIContentPolicy::TYPE_OTHER:
     context = RequestContext::Internal;
     break;
   case nsIContentPolicy::TYPE_INTERNAL_SCRIPT:
+  case nsIContentPolicy::TYPE_INTERNAL_SCRIPT_PRELOAD:
   case nsIContentPolicy::TYPE_INTERNAL_SERVICE_WORKER:
     context = RequestContext::Script;
     break;
   case nsIContentPolicy::TYPE_INTERNAL_WORKER:
     context = RequestContext::Worker;
     break;
   case nsIContentPolicy::TYPE_INTERNAL_SHARED_WORKER:
     context = RequestContext::Sharedworker;
     break;
-  case nsIContentPolicy::TYPE_IMAGE:
+  case nsIContentPolicy::TYPE_INTERNAL_IMAGE:
+  case nsIContentPolicy::TYPE_INTERNAL_IMAGE_PRELOAD:
     context = RequestContext::Image;
     break;
-  case nsIContentPolicy::TYPE_STYLESHEET:
+  case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET:
+  case nsIContentPolicy::TYPE_INTERNAL_STYLESHEET_PRELOAD:
     context = RequestContext::Style;
     break;
   case nsIContentPolicy::TYPE_INTERNAL_OBJECT:
     context = RequestContext::Object;
     break;
   case nsIContentPolicy::TYPE_INTERNAL_EMBED:
     context = RequestContext::Embed;
     break;

--- a/dom/fetch/InternalRequest.h
+++ b/dom/fetch/InternalRequest.h
@@ -38,30 +38,30 @@ namespace dom {
  * eventsource       |
  * favicon           |
  * fetch             | TYPE_FETCH
  * font              | TYPE_FONT
  * form              |
  * frame             | TYPE_INTERNAL_FRAME
  * hyperlink         |
  * iframe            | TYPE_INTERNAL_IFRAME
- * image             | TYPE_IMAGE
+ * image             | TYPE_INTERNAL_IMAGE, TYPE_INTERNAL_IMAGE_PRELOAD
  * imageset          | TYPE_IMAGESET
  * import            | Not supported by Gecko
  * internal          | TYPE_DOCUMENT, TYPE_XBL, TYPE_OTHER
  * location          |
  * manifest          | TYPE_WEB_MANIFEST
  * object            | TYPE_INTERNAL_OBJECT
  * ping              | TYPE_PING
  * plugin            | TYPE_OBJECT_SUBREQUEST
  * prefetch          |
- * script            | TYPE_INTERNAL_SCRIPT
+ * script            | TYPE_INTERNAL_SCRIPT, TYPE_INTERNAL_SCRIPT_PRELOAD
  * sharedworker      | TYPE_INTERNAL_SHARED_WORKER
  * subresource       | Not supported by Gecko
- * style             | TYPE_STYLESHEET
+ * style             | TYPE_INTERNAL_STYLESHEET, TYPE_INTERNAL_STYLESHEET_PRELOAD
  * track             | TYPE_INTERNAL_TRACK
  * video             | TYPE_INTERNAL_VIDEO
  * worker            | TYPE_INTERNAL_WORKER
  * xmlhttprequest    | TYPE_INTERNAL_XMLHTTPREQUEST
  * eventsource       | TYPE_INTERNAL_EVENTSOURCE
  * xslt              | TYPE_XSLT
  *
  * TODO: Figure out if TYPE_REFRESH maps to anything useful