ServiceWorker: Introduce ServiceWorkerDiskCacheMigrator

content/browser/appcache/appcache_disk_cache.cc

Index: content/browser/appcache/appcache_disk_cache.cc
diff --git a/content/browser/appcache/appcache_disk_cache.cc b/content/browser/appcache/appcache_disk_cache.cc
index 46f406eb6997c6815c25cd69fe669cae45799950..03d348c76bba246197ddaddad410ffccb63caa49 100644
--- a/content/browser/appcache/appcache_disk_cache.cc
+++ b/content/browser/appcache/appcache_disk_cache.cc
@@ -198,8 +198,12 @@ class AppCacheDiskCache::ActiveCall
 };
 
 AppCacheDiskCache::AppCacheDiskCache()
-    : is_disabled_(false),
-      weak_factory_(this) {
+#if defined(APPCACHE_USE_SIMPLE_CACHE)
+    : AppCacheDiskCache(true)
+#else
+    : AppCacheDiskCache(false)
+#endif
+{
 }
 
 AppCacheDiskCache::~AppCacheDiskCache() {
@@ -304,6 +308,12 @@ int AppCacheDiskCache::DoomEntry(int64 key,
   return ActiveCall::DoomEntry(weak_factory_.GetWeakPtr(), key, callback);
 }
 
+AppCacheDiskCache::AppCacheDiskCache(bool use_simple_cache)
+    : use_simple_cache_(use_simple_cache),
+      is_disabled_(false),
+      weak_factory_(this) {
+}
+
 AppCacheDiskCache::PendingCall::PendingCall()
     : call_type(CREATE),
       key(0),
@@ -333,14 +343,10 @@ int AppCacheDiskCache::Init(
   is_disabled_ = false;
   create_backend_callback_ = new CreateBackendCallbackShim(this);
 
-#if defined(APPCACHE_USE_SIMPLE_CACHE)
-  const net::BackendType backend_type = net::CACHE_BACKEND_SIMPLE;
-#else
-  const net::BackendType backend_type = net::CACHE_BACKEND_DEFAULT;
-#endif
   int rv = disk_cache::CreateCacheBackend(
       cache_type,
-      backend_type,
+      use_simple_cache_ ? net::CACHE_BACKEND_SIMPLE
+                        : net::CACHE_BACKEND_DEFAULT,
       cache_directory,
       cache_size,
       force,