Throttle script request incidents to one per user.

chrome/browser/safe_browsing/incident_reporting/script_request_incident.cc

Index: chrome/browser/safe_browsing/incident_reporting/script_request_incident.cc
diff --git a/chrome/browser/safe_browsing/incident_reporting/script_request_incident.cc b/chrome/browser/safe_browsing/incident_reporting/script_request_incident.cc
index 6aa4598083b99c2ecf8fbd7af8e99663866e84f5..7f635ea1d67091e24da4f5e7e5010c2e2cb0c871 100644
--- a/chrome/browser/safe_browsing/incident_reporting/script_request_incident.cc
+++ b/chrome/browser/safe_browsing/incident_reporting/script_request_incident.cc
@@ -26,11 +26,14 @@ IncidentType ScriptRequestIncident::GetType() const {
 }
 
 std::string ScriptRequestIncident::GetKey() const {
-  return payload()->script_request().script_digest();
+  // Use a static key in addition to a fixed digest below to ensure that only
+  // one incident per user is reported.
+  return "script_request_incident_key";

[grt (UTC plus 2), 2015/02/26 03:21:37]

i prefer simply "script_request_incident" so that the resulting pref dict entry
looks like:
{
  "script_request_incident": 42
}

i think the "_key" suffix will make it look funny, and i wouldn't want the other
preferences to laugh at it.

[robertshield, 2015/02/26 04:27:52]

Those other preferences sound like jerks to me.

[grt (UTC plus 2), 2015/02/26 04:47:18]

Their mothers didn't raise them right.

 }
 
 uint32_t ScriptRequestIncident::ComputeDigest() const {
-  // Return a constant to ensure that only one incident per digest is reported.
+  // Return a constant to ensure in addition to a fixed key above to ensure that

[grt (UTC plus 2), 2015/02/26 03:21:37]

please reduce the ensure-factor of this comment

[robertshield, 2015/02/26 04:27:52]

You can never be too sure.

[grt (UTC plus 2), 2015/02/26 04:47:18]

Indubitably.

+  // only one incident per user is reported.
   return 42;
 }