Add trace probe for chrome cleaner tasks

This CL is adding trace events under the tracing category "safe_browsing"
to determine whether or not chrome cleanup tool is running.

This is useful to determine if the cleanup tool scanning/cleaning is
affecting chrome by looking to the slow-reports. We currently can't
determine whether or not the tool is running.

R=csharp@chromium.org
CC=etienneb@chromium.org

Bug: 874448
Change-Id: I4b54ea470caab6ce63542bedd1169ab667aac008
Reviewed-on: https://chromium-review.googlesource.com/1176137Reviewed-by: Chris Sharp <csharp@chromium.org>
Commit-Queue: Etienne Bergeron <etienneb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583370}

chrome/browser/safe_browsing/chrome_cleaner/chrome_cleaner_runner_win.cc

@@ -150,6 +150,9 @@ ChromeCleanerRunner::ChromeCleanerRunner(
 
 ChromeCleanerRunner::ProcessStatus
 ChromeCleanerRunner::LaunchAndWaitForExitOnBackgroundThread() {
+  TRACE_EVENT0("safe_browsing",
+               "ChromeCleanerRunner::LaunchAndWaitForExitOnBackgroundThread");
+
   mojo::OutgoingInvitation invitation;
   std::string pipe_name = base::NumberToString(base::RandUint64());
   mojo::ScopedMessagePipeHandle request_pipe =

chrome/browser/safe_browsing/chrome_cleaner/reporter_runner_win.cc

@@ -486,6 +486,8 @@ ChromeCleanerController* GetCleanerController() {
 // external that could be shut down beforehand.
 int LaunchAndWaitForExitOnBackgroundThread(
     const SwReporterInvocation& invocation) {
+  TRACE_EVENT0("safe_browsing",
+               "ReporterRunner::LaunchAndWaitForExitOnBackgroundThread");
   if (g_testing_delegate_)
     return g_testing_delegate_->LaunchReporter(invocation);