Add data reduction proxy debug info to net-internals#bandwidth

chrome/browser/ui/webui/net_internals/net_internals_ui.cc

Index: chrome/browser/ui/webui/net_internals/net_internals_ui.cc
diff --git a/chrome/browser/ui/webui/net_internals/net_internals_ui.cc b/chrome/browser/ui/webui/net_internals/net_internals_ui.cc
index 40038be1d2c4c43e54d9fb1d1e4426810885e9fc..df345f5716a03373d427375c8f7d810e0afe3fd8 100644
--- a/chrome/browser/ui/webui/net_internals/net_internals_ui.cc
+++ b/chrome/browser/ui/webui/net_internals/net_internals_ui.cc
@@ -375,6 +375,7 @@ class NetInternalsMessageHandler::IOThreadImpl
   void OnGetServiceProviders(const base::ListValue* list);
 #endif
   void OnSetLogLevel(const base::ListValue* list);
+  void OnGetDataReductionProxyInfo(const base::ListValue* list);
 
   // ChromeNetLog::ThreadSafeObserver implementation:
   void OnAddEntry(const net::NetLog::Entry& entry) override;
@@ -578,6 +579,10 @@ void NetInternalsMessageHandler::RegisterMessages() {
       "getExtensionInfo",
       base::Bind(&NetInternalsMessageHandler::OnGetExtensionInfo,
                  base::Unretained(this)));
+  web_ui()->RegisterMessageCallback(
+      "getDataReductionProxyInfo",
+      base::Bind(&IOThreadImpl::CallbackHelper,
+                 &IOThreadImpl::OnGetDataReductionProxyInfo, proxy_));
 #if defined(OS_CHROMEOS)
   web_ui()->RegisterMessageCallback(
       "refreshSystemLogs",
@@ -1292,6 +1297,27 @@ void NetInternalsMessageHandler::IOThreadImpl::OnSetLogLevel(
       this, static_cast<net::NetLog::LogLevel>(log_level));
 }
 
+void NetInternalsMessageHandler::IOThreadImpl::OnGetDataReductionProxyInfo(
+    const base::ListValue* list) {
+  DCHECK(!list);
+  net::HttpNetworkSession* http_network_session =
+      GetHttpNetworkSession(main_context_getter_->GetURLRequestContext());
+
+  base::Value* data_reduction_proxy_info = NULL;

[mmenke, 2014/12/03 18:58:46]

I believe nullptr is now preferred

[jeremyim, 2014/12/03 20:57:26]

Done.

+  if (http_network_session) {
+    ChromeNetworkDelegate* network_delegate =
+        static_cast<ChromeNetworkDelegate*>(
+            http_network_session->network_delegate());

[mmenke, 2014/12/03 18:58:46]

This is a problem.  See https://codereview.chromium.org/734263003/.

In general, casting is just a bad idea.

[jeremyim, 2014/12/03 20:57:26]

Yeah, I'm not too thrilled about it either, and the current implementation would
have to change based on Megan's CL (and whose CL landed first).

Some alternatives that come to mind:
- Add specific methods on NetworkDelegate for the items we are static casting
(SessionNetworkStatsInfoToValue on line 1074, DataReductionProxyInfoToValue)
which return nullptr or a null base::Value
- Add a generic "base::Value* GetCustomInfo(std::string info_type)" method on
NetworkDelegate which allows the different implementations to return their
specific information
- Some other way of plumbing DataReductionProxyEventStore here; but I'm not sure
what that would look like

+
+    if (network_delegate)
+      data_reduction_proxy_info =
+        network_delegate->DataReductionProxyInfoToValue();
+  }
+
+  SendJavascriptCommand(
+      "receivedDataReductionProxyInfo", data_reduction_proxy_info);
+}
+
 // Note that unlike other methods of IOThreadImpl, this function
 // can be called from ANY THREAD.
 void NetInternalsMessageHandler::IOThreadImpl::OnAddEntry(