Added incident report for variations seed signature mismatch.

chrome/browser/safe_browsing/incident_reporting/variations_seed_signature_analyzer.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/safe_browsing/incident_reporting/variations_seed_signature_analyzer.h"
+
+#include <string>
+
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/metrics/variations/variations_service.h"
+#include "chrome/browser/safe_browsing/safe_browsing_service.h"
+#include "chrome/common/safe_browsing/csd.pb.h"
+
+namespace safe_browsing {
+
+void RegisterVariationsSeedSignatureAnalysis() {
+  scoped_refptr<SafeBrowsingService> safe_browsing_service(
+      g_browser_process->safe_browsing_service());
+
+  safe_browsing_service->RegisterDelayedAnalysisCallback(
+      base::Bind(&VerifyVariationsSeedSignature));
+}
+
+void VerifyVariationsSeedSignature(const AddIncidentCallback& callback) {
+  std::string invalid_signature = g_browser_process->variations_service()

[Alexei Svitkine (slow), 2014/10/15 14:53:07]

Nit: Wrap after =

[Georges Khalil, 2014/10/15 16:53:19]

I tried, it won't fit. This is the output of git cl format.

+                                      ->GetInvalidVariationsSeedSignature();

[Alexei Svitkine (slow), 2014/10/15 14:55:56]

Actually, one other thing - g_browser_process->variations_service() may be NULL
- for example if it's a Chromium build. You should add an early return in that
case.

[Georges Khalil, 2014/10/15 16:53:19]

Done.

+  if (!invalid_signature.empty()) {
+    scoped_ptr<safe_browsing::ClientIncidentReport_IncidentData> incident_data(
+        new safe_browsing::ClientIncidentReport_IncidentData());
+    safe_browsing::

[Alexei Svitkine (slow), 2014/10/15 14:53:07]

Nit: No need for namespace here.

+        ClientIncidentReport_IncidentData_VariationsSeedSignatureIncident*
+            variations_seed_signature =
+                incident_data->mutable_variations_seed_signature();
+    variations_seed_signature->set_variations_seed_signature(invalid_signature);
+    callback.Run(incident_data.Pass());
+  }
+}
+
+}  // namespace safe_browsing