[CacheStorage] Temporarily preserve recently opened caches from CacheStorageDispatcherHost

content/browser/cache_storage/cache_storage_dispatcher_host.h

Index: content/browser/cache_storage/cache_storage_dispatcher_host.h
diff --git a/content/browser/cache_storage/cache_storage_dispatcher_host.h b/content/browser/cache_storage/cache_storage_dispatcher_host.h
index d937bac03486e5343e5a002e939dcf5575774754..87f7fac22d8bb9e15af400ee0968239feeb53fdc 100644
--- a/content/browser/cache_storage/cache_storage_dispatcher_host.h
+++ b/content/browser/cache_storage/cache_storage_dispatcher_host.h
@@ -155,6 +155,8 @@ class CONTENT_EXPORT CacheStorageDispatcherHost : public BrowserMessageFilter {
       std::unique_ptr<CacheStorageCacheHandle> cache_handle,
       CacheStorageError error);
 
+  void StopPreservingCache(const CacheStorageCache* cache);
+
   // Hangs onto a cache handle. Returns a unique cache_id. Call
   // DropCacheReference when the reference is no longer needed.
   CacheID StoreCacheReference(
@@ -166,6 +168,11 @@ class CONTENT_EXPORT CacheStorageDispatcherHost : public BrowserMessageFilter {
   void StoreBlobDataHandle(const storage::BlobDataHandle& blob_data_handle);
   void DropBlobDataHandle(const std::string& uuid);
 
+  // Store handles to recently opened caches for a short period in case they're
+  // used again in the near future.
+  std::map<const CacheStorageCache*, std::unique_ptr<CacheStorageCacheHandle>>
+      preserved_cache_handles_;
+
   IDToCacheMap id_to_cache_map_;
   CacheID next_cache_id_ = 0;