SimpleCache: merge the first and second stream in one file

net/disk_cache/simple/simple_util.h

Index: net/disk_cache/simple/simple_util.h
diff --git a/net/disk_cache/simple/simple_util.h b/net/disk_cache/simple/simple_util.h
index 3bb80b9540238393aa859a9791e6a4faab7d458f..ef7119b70960d4ee6e4f6ea525d25cdd3b2ff6a2 100644
--- a/net/disk_cache/simple/simple_util.h
+++ b/net/disk_cache/simple/simple_util.h
@@ -56,12 +56,21 @@ NET_EXPORT_PRIVATE int32 GetDataSizeFromKeyAndFileSize(const std::string& key,
 // returns the number of bytes in the file.
 NET_EXPORT_PRIVATE int64 GetFileSizeFromKeyAndDataSize(const std::string& key,
                                                        int32 data_size);
+// Given the stream index, returns the number of the file the stream is stored
+// in.
+NET_EXPORT_PRIVATE int GetFileIndexFromStreamIndex(int stream_index);
+
+// Given the data size for all streams and a file index, gives the data maximum
+// offset.
+NET_EXPORT_PRIVATE int GetMaximumDataOffset(int file_index,
+                                            const int data_size[]);
 
 // Given the key to an entry, and an offset into a stream on that entry, returns
 // the file offset corresponding to |data_offset|.
-NET_EXPORT_PRIVATE int64 GetFileOffsetFromKeyAndDataOffset(
-    const std::string& key,
-    int data_offset);
+NET_EXPORT_PRIVATE int64 GetFileOffsetFromDataOffset(const std::string& key,
+                                                     int data_offset,
+                                                     int index,
+                                                     int stream_1_size);
 
 // Fills |out_time| with the time the file last modified time.
 // TODO(gavinp): Remove this function.