http_cache: reorder states

net/http/http_cache_transaction.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file declares HttpCache::Transaction, a private class of HttpCache so
 // it should only be included by http_cache.cc
 
 #ifndef NET_HTTP_HTTP_CACHE_TRANSACTION_H_
 #define NET_HTTP_HTTP_CACHE_TRANSACTION_H_
 
@@ skipping 152 matching lines @@
   // Helper struct to pair a header name with its value, for
   // headers used to validate cache entries.
   struct ValidationHeaders {
     ValidationHeaders() : initialized(false) {}
 
     std::string values[kNumValidationHeaders];
     bool initialized;
   };
 
   enum State {
+    // Normally, states are traversed in approximately this order.
     STATE_NONE,
     STATE_GET_BACKEND,
     STATE_GET_BACKEND_COMPLETE,
+    STATE_INIT_ENTRY,
+    STATE_OPEN_ENTRY,
+    STATE_OPEN_ENTRY_COMPLETE,
+    STATE_DOOM_ENTRY,
+    STATE_DOOM_ENTRY_COMPLETE,
+    STATE_CREATE_ENTRY,
+    STATE_CREATE_ENTRY_COMPLETE,
+    STATE_ADD_TO_ENTRY,
+    STATE_ADD_TO_ENTRY_COMPLETE,
+    STATE_CACHE_READ_RESPONSE,
+    STATE_CACHE_READ_RESPONSE_COMPLETE,
+    STATE_TOGGLE_UNUSED_SINCE_PREFETCH,
+    STATE_TOGGLE_UNUSED_SINCE_PREFETCH_COMPLETE,
+    STATE_CACHE_DISPATCH_VALIDATION,
+    STATE_CACHE_QUERY_DATA,
+    STATE_CACHE_QUERY_DATA_COMPLETE,
+    STATE_START_PARTIAL_CACHE_VALIDATION,
+    STATE_COMPLETE_PARTIAL_CACHE_VALIDATION,
     STATE_SEND_REQUEST,
     STATE_SEND_REQUEST_COMPLETE,
     STATE_SUCCESSFUL_SEND_REQUEST,
-    STATE_NETWORK_READ,
-    STATE_NETWORK_READ_COMPLETE,
-    STATE_INIT_ENTRY,
-    STATE_OPEN_ENTRY,
-    STATE_OPEN_ENTRY_COMPLETE,
-    STATE_CREATE_ENTRY,
-    STATE_CREATE_ENTRY_COMPLETE,
-    STATE_DOOM_ENTRY,
-    STATE_DOOM_ENTRY_COMPLETE,
-    STATE_ADD_TO_ENTRY,
-    STATE_ADD_TO_ENTRY_COMPLETE,
-    STATE_START_PARTIAL_CACHE_VALIDATION,
-    STATE_COMPLETE_PARTIAL_CACHE_VALIDATION,
     STATE_UPDATE_CACHED_RESPONSE,
     STATE_UPDATE_CACHED_RESPONSE_COMPLETE,
     STATE_OVERWRITE_CACHED_RESPONSE,
+    STATE_CACHE_WRITE_RESPONSE,
+    STATE_CACHE_WRITE_TRUNCATED_RESPONSE,
+    STATE_CACHE_WRITE_RESPONSE_COMPLETE,
     STATE_TRUNCATE_CACHED_DATA,
     STATE_TRUNCATE_CACHED_DATA_COMPLETE,
     STATE_TRUNCATE_CACHED_METADATA,
     STATE_TRUNCATE_CACHED_METADATA_COMPLETE,
     STATE_PARTIAL_HEADERS_RECEIVED,
-    STATE_CACHE_READ_RESPONSE,
-    STATE_CACHE_READ_RESPONSE_COMPLETE,
-    STATE_CACHE_DISPATCH_VALIDATION,
-    STATE_TOGGLE_UNUSED_SINCE_PREFETCH,
-    STATE_TOGGLE_UNUSED_SINCE_PREFETCH_COMPLETE,
-    STATE_CACHE_WRITE_RESPONSE,
-    STATE_CACHE_WRITE_TRUNCATED_RESPONSE,
-    STATE_CACHE_WRITE_RESPONSE_COMPLETE,
     STATE_CACHE_READ_METADATA,
     STATE_CACHE_READ_METADATA_COMPLETE,
-    STATE_CACHE_QUERY_DATA,
-    STATE_CACHE_QUERY_DATA_COMPLETE,
+
+    // These states are entered from Read/Write
+    STATE_NETWORK_READ,
+    STATE_NETWORK_READ_COMPLETE,
     STATE_CACHE_READ_DATA,
     STATE_CACHE_READ_DATA_COMPLETE,
     STATE_CACHE_WRITE_DATA,
     STATE_CACHE_WRITE_DATA_COMPLETE
   };
 
   // Used for categorizing transactions for reporting in histograms. Patterns
   // cover relatively common use cases being measured and considered for
   // optimization. Many use cases that are more complex or uncommon are binned
   // as PATTERN_NOT_COVERED, and details are not reported.
@@ skipping 262 matching lines @@
   BeforeProxyHeadersSentCallback before_proxy_headers_sent_callback_;
 
   base::WeakPtrFactory<Transaction> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Transaction);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_CACHE_TRANSACTION_H_