Broadcast a D-Bus message whenever a user-space process crash happens.

crash_reporter.cc

Index: crash_reporter.cc
diff --git a/crash_reporter.cc b/crash_reporter.cc
index 951d3fae3d4ecfc96104f949b1c9cf1d3a19545b..e283322dab15b1c2c1640866755bd6bf5f7fe182 100644
--- a/crash_reporter.cc
+++ b/crash_reporter.cc
@@ -77,6 +77,18 @@ static void CountUserCrash() {
   s_metrics_lib.SendEnumToUMA(std::string(kCrashCounterHistogram),
                               CRASH_KIND_USER,
                               CRASH_KIND_MAX);
+
+  // Announce through D-Bus whenever a user crash happens. This is
+  // used by the metrics daemon to log active use time between
+  // crashes.
+  //
+  // This could be done more efficiently by explicit fork/exec or
+  // using a dbus library directly. However, this should run
+  // relatively rarely and longer term we may need to implement a
+  // better way to do this that doesn't rely on D-Bus.
+  int status __attribute__((unused)) =
+      system("/usr/bin/dbus-send --type=signal --system / "
+             "org.chromium.CrashReporter.UserCrash");
 }
 
 int main(int argc, char *argv[]) {