Propagate the encoded data length through OnDownloadData delegate method

webkit/child/resource_loader_bridge.h

Index: webkit/child/resource_loader_bridge.h
diff --git a/webkit/child/resource_loader_bridge.h b/webkit/child/resource_loader_bridge.h
index 160bc846a594cd4225e9f0703ec48ecdde1e01ae..f1bedecb94d8907b1a595283f56f4900c355fe95 100644
--- a/webkit/child/resource_loader_bridge.h
+++ b/webkit/child/resource_loader_bridge.h
@@ -153,13 +153,18 @@ class ResourceLoaderBridge {
     // called multiple times or not at all if an error occurs.  This method is
     // only called if RequestInfo::download_to_file was set to true, and in
     // that case, OnReceivedData will not be called.
-    virtual void OnDownloadedData(int len) = 0;
+    // The encoded_data_length is the length of the encoded data transferred
+    // over the network, which could be different from data length (e.g. for
+    // gzipped content), or -1 if unknown. It is only valid while devtools are
+    // attached. Otherwise it becomes -1.
+    virtual void OnDownloadedData(int len, int encoded_data_length) = 0;
 
     // Called when a chunk of response data is available. This method may
     // be called multiple times or not at all if an error occurs.
     // The encoded_data_length is the length of the encoded data transferred
     // over the network, which could be different from data length (e.g. for
-    // gzipped content), or -1 if if unknown.
+    // gzipped content), or -1 if unknown. It is only valid while devtools are
+    // attached. Otherwise it becomes -1.
     virtual void OnReceivedData(const char* data,
                                 int data_length,
                                 int encoded_data_length) = 0;