Webfont CORS-enabled fetching with fallback

Source/core/css/CSSFontFaceSrcValue.cpp

Index: Source/core/css/CSSFontFaceSrcValue.cpp
diff --git a/Source/core/css/CSSFontFaceSrcValue.cpp b/Source/core/css/CSSFontFaceSrcValue.cpp
index 5ccf7547707efc0f79d2e69841d9ace072da92cb..00321c7d8b7c72ef3245d342103acb60d5ea949a 100644
--- a/Source/core/css/CSSFontFaceSrcValue.cpp
+++ b/Source/core/css/CSSFontFaceSrcValue.cpp
@@ -88,10 +88,21 @@ bool CSSFontFaceSrcValue::hasFailedOrCanceledSubresources() const
     return m_fetched->loadFailedOrCanceled();
 }
 
+static bool shouldSetCrossOriginAccessControl(const KURL& resource, SecurityOrigin* securityOrigin)
+{
+    if (resource.isLocalFile() || resource.protocolIsData())
+        return false;
+    return !securityOrigin->canRequest(resource);

[Kunihiko Sakamoto, 2014/04/09 10:24:18]

I'm not familiar with this, but doesn't this return false for cross-origin
requests?

[bashi, 2014/04/10 03:40:56]

In short, canRequest() returns true when |resource| is the same origin as
|securityOrigin|. I think we want to set "Origin" header when |resource| isn't
the same origin.

[Kunihiko Sakamoto, 2014/04/10 05:49:24]

Oh, I missed the ! operator. So we add Origin header only for cross-origin
request. Is that consistent with other CORS-subjected resources? FF seems to add
Origin header for same-origin font requests as well.

[Kunihiko Sakamoto, 2014/04/10 06:53:09]

Nevermind - FireFox does not add Origin header for same-origin requests. I was
looking at wrong log.

+}
+
 FontResource* CSSFontFaceSrcValue::fetch(Document* document)
 {
     if (!m_fetched) {
         FetchRequest request(ResourceRequest(document->completeURL(m_resource)), FetchInitiatorTypeNames::css);
+        SecurityOrigin* securityOrigin = document->securityOrigin();
+        if (shouldSetCrossOriginAccessControl(request.url(), securityOrigin)) {
+            request.setCrossOriginAccessControl(securityOrigin, DoNotAllowStoredCredentials);
+        }
         m_fetched = document->fetcher()->fetchFont(request);
     }
     return m_fetched.get();