Move net-export thread-hopping code into NetLogFileWriter and add IO polled data.

components/cronet/android/cronet_url_request_context_adapter.cc

Index: components/cronet/android/cronet_url_request_context_adapter.cc
diff --git a/components/cronet/android/cronet_url_request_context_adapter.cc b/components/cronet/android/cronet_url_request_context_adapter.cc
index 96d1463a4bdc16b315d72b379e5890799e82a36d..42307f05eca2a3d00e1fd7f22ae29191ec52abb7 100644
--- a/components/cronet/android/cronet_url_request_context_adapter.cc
+++ b/components/cronet/android/cronet_url_request_context_adapter.cc
@@ -55,6 +55,7 @@
 #include "net/http/http_auth_handler_factory.h"
 #include "net/http/http_server_properties_manager.h"
 #include "net/log/file_net_log_observer.h"
+#include "net/log/net_log_util.h"
 #include "net/log/write_to_file_net_log_observer.h"
 #include "net/nqe/external_estimate_provider.h"
 #include "net/proxy/proxy_config_service_android.h"
@@ -946,7 +947,7 @@ void CronetURLRequestContextAdapter::StartNetLogToBoundedFileOnNetworkThread(
 void CronetURLRequestContextAdapter::StopBoundedFileNetLogOnNetworkThread() {
   DCHECK(GetNetworkTaskRunner()->BelongsToCurrentThread());
   bounded_file_observer_->StopObserving(
-      context_.get(),
+      net::GetNetInfo(context_.get(), net::NET_INFO_ALL_SOURCES),
       base::Bind(&CronetURLRequestContextAdapter::StopNetLogCompleted,
                  base::Unretained(this)));
   bounded_file_observer_.reset();