Prerender: Disable prefetch if there's an appcache.

content/public/browser/appcache_service.h

Index: content/public/browser/appcache_service.h
diff --git a/content/public/browser/appcache_service.h b/content/public/browser/appcache_service.h
index 5daaa5858581f3d8bb3b20a9391a5ed1cc596510..30d113c04fb83c41ffc3ae0d311af2d28b2ae565 100644
--- a/content/public/browser/appcache_service.h
+++ b/content/public/browser/appcache_service.h
@@ -14,6 +14,10 @@
 #include "content/public/common/appcache_info.h"
 #include "net/base/completion_callback.h"
 
+namespace net {
+class URLRequest;
+}  // namespace net
+
 namespace content {
 
 // Refcounted container to avoid copying the collection in callbacks.
@@ -47,6 +51,8 @@ class CONTENT_EXPORT AppCacheService {
   virtual void DeleteAppCacheGroup(const GURL& manifest_url,
                                    const net::CompletionCallback& callback) = 0;
 
+  static bool URLRequestHasActiveAppCache(net::URLRequest* request);

[michaeln, 2017/03/27 23:27:45]

If we can avoid adding this to the content public api, we probably should.

+
  protected:
   virtual ~AppCacheService() {}
 };