Webfont CORS-enabled fetching with fallback

Source/core/css/RemoteFontFaceSource.cpp

Index: Source/core/css/RemoteFontFaceSource.cpp
diff --git a/Source/core/css/RemoteFontFaceSource.cpp b/Source/core/css/RemoteFontFaceSource.cpp
index 9b15954c7a9aa06f6e7b13d21cf7c3732c9a05b7..565d1158e3eb8fd5299b5d44dbeddd7ccc68ad87 100644
--- a/Source/core/css/RemoteFontFaceSource.cpp
+++ b/Source/core/css/RemoteFontFaceSource.cpp
@@ -5,8 +5,11 @@
 #include "config.h"
 #include "core/css/RemoteFontFaceSource.h"
 
+#include "FetchInitiatorTypeNames.h"
 #include "core/css/CSSCustomFontData.h"
 #include "core/css/CSSFontFace.h"
+#include "core/css/CSSFontSelector.h"
+#include "core/fetch/ResourceFetcher.h"
 #include "platform/fonts/FontCache.h"
 #include "platform/fonts/FontDescription.h"
 #include "platform/fonts/SimpleFontData.h"
@@ -82,6 +85,24 @@ void RemoteFontFaceSource::fontLoadWaitLimitExceeded(FontResource*)
     m_histograms.recordFallbackTime(m_font.get());
 }
 
+void RemoteFontFaceSource::corsFailed(FontResource*)
+{
+    pruneTable();
+
+    if (m_face) {
+        Document* document = m_face->fontSelector() ? m_face->fontSelector()->document() : 0;
+        if (document) {
+            FetchRequest request(ResourceRequest(m_font->url()), FetchInitiatorTypeNames::css);
+            m_font->removeClient(this);
+            m_font = document->fetcher()->fetchFont(request);
+            m_font->addClient(this);
+            m_face->fontSelector()->beginLoadingFontSoon(m_font.get());
+        } else {
+            m_face->fontLoaded(this);
+        }
+    }
+}
+
 PassRefPtr<SimpleFontData> RemoteFontFaceSource::createFontData(const FontDescription& fontDescription)
 {
     if (!isLoaded())
@@ -156,6 +177,12 @@ void RemoteFontFaceSource::FontLoadHistograms::recordRemoteFont(const FontResour
             : font->response().wasCached() ? Hit
             : Miss;
         blink::Platform::current()->histogramEnumeration("WebFont.CacheHit", histogramValue, CacheHitEnumMax);
+
+        if (!font->errorOccurred()) {
+            enum { CORSSuccess, CORSFail, CORSEnumMax };
+            int corsValue = font->options().corsEnabled == IsCORSEnabled ? CORSSuccess : CORSFail;
+            blink::Platform::current()->histogramEnumeration("WebFont.CORSSuccess", corsValue, CORSEnumMax);
+        }
     }
 }