Bug 1077312 - Clean up Accept headers on @font-face HTTP requests. r=mcmanus

layout/style/FontFaceSet.cpp

@@ -439,8 +439,15 @@ FontFaceSet::StartLoad(gfxUserFontEntry* aUserFontEntry,
 #endif
 
   nsCOMPtr<nsIHttpChannel> httpChannel(do_QueryInterface(channel));
-  if (httpChannel)
+  if (httpChannel) {
     httpChannel->SetReferrer(aFontFaceSrc->mReferrer);
+    nsAutoCString accept("application/font-woff;q=0.9,*/*;q=0.8");
+    if (Preferences::GetBool(GFX_PREF_WOFF2_ENABLED)) {
+      accept.Insert(NS_LITERAL_CSTRING("application/font-woff2;q=1.0,"), 0);
+    }
+    httpChannel->SetRequestHeader(NS_LITERAL_CSTRING("Accept"),
+                                  accept, false);
+  }
   nsCOMPtr<nsISupportsPriority> priorityChannel(do_QueryInterface(channel));
   if (priorityChannel) {
     priorityChannel->AdjustPriority(nsISupportsPriority::PRIORITY_HIGH);