Teach CrOS's OfflineResourceThrottle about ServiceWorkers so it know longer presents its offline in…

content/public/browser/service_worker_context.h

Index: content/public/browser/service_worker_context.h
diff --git a/content/public/browser/service_worker_context.h b/content/public/browser/service_worker_context.h
index 94ab73f67e2d59d2a68035e03932f6f5b4b50b8c..22c989b4ce8254ddfd423421af59aec9cec2f69c 100644
--- a/content/public/browser/service_worker_context.h
+++ b/content/public/browser/service_worker_context.h
@@ -11,8 +11,13 @@
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "content/public/browser/service_worker_usage_info.h"
+#include "net/base/completion_callback.h"
 #include "url/gurl.h"
 
+namespace net {
+class URLRequest;
+}
+
 namespace content {
 
 // Represents the per-StoragePartition ServiceWorker data.
@@ -36,6 +41,10 @@ class ServiceWorkerContext {
   // Must be called from the IO thread.
   static bool IsExcludedHeaderNameForFetchEvent(const std::string& header_name);
 
+  // Retrieves the ServiceWorkerContext, if any, associated with |request|.
+  CONTENT_EXPORT static ServiceWorkerContext* GetServiceWorkerContext(
+      net::URLRequest* request);
+
   // Equivalent to calling navigator.serviceWorker.register(script_url, {scope:
   // pattern}) from a renderer, except that |pattern| is an absolute URL instead
   // of relative to some current origin.  |callback| is passed true when the JS
@@ -64,6 +73,13 @@ class ServiceWorkerContext {
 
   // TODO(jyasskin): Provide a way to SendMessage to a Scope.
 
+  // Determines if a request for 'url' can be satisfied while offline.

[falken, 2014/12/16 08:16:50]

nit: use |url| style instead of 'url'

+  // This method always completes asynchronously.
+  virtual void CanHandleMainResourceOffline(const GURL& url,
+                                            const GURL& first_party,
+                                            const net::CompletionCallback&
+                                            callback) = 0;
+
   // Methods used in response to browsing data and quota manager requests.
   virtual void GetAllOriginsInfo(const GetUsageInfoCallback& callback) = 0;
   virtual void DeleteForOrigin(const GURL& origin_url) = 0;