Warn user in case extension delays network traffic too much.

chrome/browser/extensions/extension_webrequest_api.cc

Index: chrome/browser/extensions/extension_webrequest_api.cc
diff --git a/chrome/browser/extensions/extension_webrequest_api.cc b/chrome/browser/extensions/extension_webrequest_api.cc
index 208554ab237ce310128d47b92956e1261391a06e..5aef46bf0e7b73b45428e3df6ea32fbd742b6340 100644
--- a/chrome/browser/extensions/extension_webrequest_api.cc
+++ b/chrome/browser/extensions/extension_webrequest_api.cc
@@ -6,19 +6,21 @@
 
 #include <algorithm>
 
+#include "base/bind.h"
 #include "base/json/json_writer.h"
 #include "base/metrics/histogram.h"
 #include "base/string_number_conversions.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/extension_event_router.h"
 #include "chrome/browser/extensions/extension_info_map.h"
 #include "chrome/browser/extensions/extension_prefs.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_tab_id_map.h"
 #include "chrome/browser/extensions/extension_webrequest_api_constants.h"
-#include "chrome/browser/extensions/extension_webrequest_time_tracker.h"
 #include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/browser/renderer_host/chrome_render_message_filter.h"
 #include "chrome/browser/renderer_host/web_cache_manager.h"
 #include "chrome/common/extensions/extension.h"
@@ -141,6 +143,28 @@ class NetLogModificationParameter : public NetLogExtensionIdParameter {
   DISALLOW_COPY_AND_ASSIGN(NetLogModificationParameter);
 };
 
+// Handles ExtensionWebRequestTimeTrackerDelegate calls on UI thread.
+void NotifyExcessiveDelaysOnUI(void* profile,
+                               size_t num_delayed_messages,
+                               size_t total_num_messages,
+                               std::set<std::string> extension_ids) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  Profile* p = reinterpret_cast<Profile*>(profile);
+  if (!p || !g_browser_process->profile_manager()->IsValidProfile(p))
+    return;
+
+  ExtensionService* extension_service = p->GetExtensionService();
+
+  // We don't need to warn more than once.
+  if (extension_service->HasWarning(ExtensionServiceWarning::kNetworkDelay))
+    return;
+
+  // Override previous warning
+  extension_service->SetWarning(
+      ExtensionServiceWarning(ExtensionServiceWarning::kNetworkDelay,
+                              extension_ids));
+}
+
 // Returns the frame ID as it will be passed to the extension:
 // 0 if the navigation happens in the main frame, or the frame ID
 // modulo 32 bits otherwise.
@@ -466,11 +490,33 @@ ExtensionWebRequestEventRouter* ExtensionWebRequestEventRouter::GetInstance() {
 
 ExtensionWebRequestEventRouter::ExtensionWebRequestEventRouter()
     : request_time_tracker_(new ExtensionWebRequestTimeTracker) {
+  request_time_tracker_->SetDelegate(this);
 }
 
 ExtensionWebRequestEventRouter::~ExtensionWebRequestEventRouter() {
 }
 
+void ExtensionWebRequestEventRouter::NotifyExcessiveDelays(
+    void* profile,
+    size_t num_delayed_messages,
+    size_t total_num_messages,
+    const std::set<std::string>& extension_ids) {
+  BrowserThread::PostTask(
+      BrowserThread::UI,
+      FROM_HERE,
+      base::Bind(&NotifyExcessiveDelaysOnUI,
+                 profile, num_delayed_messages, total_num_messages,
+                 extension_ids));
+}
+
+void ExtensionWebRequestEventRouter::NotifyModerateDelays(
+    void* profile,
+    size_t num_delayed_messages,
+    size_t total_num_messages,
+    const std::set<std::string>& extension_ids) {
+  // We do not report these.

[Matt Perry, 2011/10/06 22:55:54]

why not?

The goal of the 2 buckets was to catch 2 bad cases:
- excessive: an extension takes a really long time on a small number of
requests, noticeably slowing down a couple page loads.
- moderate: an extension slows down many requests a medium amount. it might not
be noticeable in any given instance, but chrome "feels" slower overall.

[battre, 2011/10/07 14:09:24]

Done.

I had not understood this properly before. Thanks.

+}
+
 int ExtensionWebRequestEventRouter::OnBeforeRequest(
     void* profile,
     ExtensionInfoMap* extension_info_map,
@@ -486,7 +532,8 @@ int ExtensionWebRequestEventRouter::OnBeforeRequest(
 
   request_time_tracker_->LogRequestStartTime(request->identifier(),
                                              base::Time::Now(),
-                                             request->url());
+                                             request->url(),
+                                             profile);
 
   int extra_info_spec = 0;
   std::vector<const EventListener*> listeners =