Bypass android download manager if response is not yet received

chrome/browser/android/intercept_download_resource_throttle.cc

Index: chrome/browser/android/intercept_download_resource_throttle.cc
diff --git a/chrome/browser/android/intercept_download_resource_throttle.cc b/chrome/browser/android/intercept_download_resource_throttle.cc
index d95674418f381ac815c41fb6184ab1543aa83641..d71bdcf20aa36fff589fc47bacf6b2c9f6843630 100644
--- a/chrome/browser/android/intercept_download_resource_throttle.cc
+++ b/chrome/browser/android/intercept_download_resource_throttle.cc
@@ -53,14 +53,16 @@ void InterceptDownloadResourceThrottle::ProcessDownloadRequest() {
   if (request_->method() != net::HttpRequestHeaders::kGetMethod)
     return;
 
+  net::HttpRequestHeaders headers;
+  if (!request_->GetFullRequestHeaders(&headers))
+    return;
+
   // In general, if the request uses HTTP authorization, either with the origin
   // or a proxy, then the network stack should handle the download. The one
   // exception is a request that is fetched via the Chrome Proxy and does not
   // authenticate with the origin.
   if (request_->response_info().did_use_http_auth) {
 #if defined(SPDY_PROXY_AUTH_ORIGIN)
-    net::HttpRequestHeaders headers;
-    request_->GetFullRequestHeaders(&headers);
     if (headers.HasHeader(net::HttpRequestHeaders::kAuthorization) ||
         !(request_->response_info().headers &&
             data_reduction_proxy::HasDataReductionProxyViaHeader(