Don't wait for AppCache for link rel preloads

third_party/WebKit/Source/core/loader/LinkLoader.h

Index: third_party/WebKit/Source/core/loader/LinkLoader.h
diff --git a/third_party/WebKit/Source/core/loader/LinkLoader.h b/third_party/WebKit/Source/core/loader/LinkLoader.h
index a9f0b1dddf04549c846655605083454233b31436..ac40af66dfd05c796fdd62338df12e67c8cc6455 100644
--- a/third_party/WebKit/Source/core/loader/LinkLoader.h
+++ b/third_party/WebKit/Source/core/loader/LinkLoader.h
@@ -75,7 +75,10 @@ public:
     void released();
     bool loadLink(const LinkRelAttribute&, CrossOriginAttributeValue, const String& type, const String& as, const String& media, const KURL&, Document&, const NetworkHintsInterface&);
     enum CanLoadResources { OnlyLoadResources, DoNotLoadResources, LoadResourcesAndPreconnect };
-    static void loadLinksFromHeader(const String& headerValue, const KURL& baseURL, Document*, const NetworkHintsInterface&, CanLoadResources, ViewportDescriptionWrapper*);
+    // Media links cannot be preloaded until the first chunk is parsed. The rest

[Yoav Weiss, 2016/07/22 08:43:28]

"well, actually" warning: their preloading is waiting until the first chunk is
tokenized, not necessarily parsed. But at the same time, we seem to be using
"parsed" all over the place (e.g. notifyPendingParsedChunks is called from
sendTokensToMainThread, where m_parsedChunkQueue is used to store tokenized
chunks...)

[Charlie Harrison, 2016/07/22 14:03:22]

You're right. It's better to be clear here, and using "parsed" for tokenized
confuses me as well :) If that's the case, then why do we only load links from
headers *after* constructTreeFromCompactHTMLToken (parsing) is called?

We could move that call into notifyPendingParsedChunks if all it needs is the
chunk viewport.

+    // can be preloaded at commit time.
+    enum MediaPreloadPolicy { LoadAll, OnlyLoadNonMedia, OnlyLoadMedia };
+    static void loadLinksFromHeader(const String& headerValue, const KURL& baseURL, Document*, const NetworkHintsInterface&, CanLoadResources, MediaPreloadPolicy, ViewportDescriptionWrapper*);
     static bool getResourceTypeFromAsAttribute(const String& as, Resource::Type&);
 
     DECLARE_TRACE();