Add method getAllHeaders to HttpUrlRequest.

components/cronet/android/url_request_peer.h

Index: components/cronet/android/url_request_peer.h
diff --git a/components/cronet/android/url_request_peer.h b/components/cronet/android/url_request_peer.h
index e8d79a6d43e0f6988472e2172ce04d5613518c2c..5aa265de2b3e4589386bf391737a3fcff827d842 100644
--- a/components/cronet/android/url_request_peer.h
+++ b/components/cronet/android/url_request_peer.h
@@ -18,6 +18,7 @@
 
 namespace net {
 class GrowableIOBuffer;
+class HttpResponseHeaders;
 class UploadDataStream;
 }  // namespace net
 
@@ -90,6 +91,9 @@ class URLRequestPeer : public net::URLRequest::Delegate {
   // Returns the value of the specified response header.
   std::string GetHeader(const std::string& name) const;
 
+  // Get all response headers, as a HttpResponseHeaders object.
+  net::HttpResponseHeaders* GetResponseHeaders() const;
+
   // Returns the overall number of bytes read.
   size_t bytes_read() const { return bytes_read_; }