Add trace events to RulesetService

Add trace of prefs format and content version at RulesetService
creation. Add trace of invalid Indexed Ruleset file read.

Bug: 721512
Change-Id: I6809a2cccb8903889b74e64a8c08788ff3c8422a
Reviewed-on: https://chromium-review.googlesource.com/1108242Reviewed-by: Charlie Harrison <csharrison@chromium.org>
Commit-Queue: John Delaney <johnidel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#570227}

components/subresource_filter/content/browser/verified_ruleset_dealer.cc

@@ -30,6 +30,9 @@ base::File VerifiedRulesetDealer::OpenAndSetRulesetFile(
   // there are handles to it still open.
   base::File file(file_path, base::File::FLAG_OPEN | base::File::FLAG_READ |
                                  base::File::FLAG_SHARE_DELETE);
+  TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("loading"),
+               "VerifiedRulesetDealer::OpenAndSetRulesetFile", "file_valid",
+               file.IsValid());
   if (file.IsValid())
     SetRulesetFile(file.Duplicate());
   return file;

components/subresource_filter/core/browser/ruleset_service.cc

@@ -20,6 +20,8 @@
 #include "base/strings/string_number_conversions.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread_restrictions.h"
+#include "base/trace_event/trace_event.h"
+#include "base/trace_event/trace_event_argument.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
 #include "components/subresource_filter/core/browser/copying_file_stream.h"
@@ -136,6 +138,14 @@ void IndexedRulesetVersion::SaveToPrefs(PrefService* local_state) const {
                          content_version);
 }
 
+std::unique_ptr<base::trace_event::TracedValue>
+IndexedRulesetVersion::ToTracedValue() const {
+  auto value = std::make_unique<base::trace_event::TracedValue>();
+  value->SetString("content_version", content_version);
+  value->SetInteger("format_version", format_version);
+  return value;
+}
+
 // IndexedRulesetLocator ------------------------------------------------------
 
 // static
@@ -227,6 +237,9 @@ RulesetService::RulesetService(
 
   IndexedRulesetVersion most_recently_indexed_version;
   most_recently_indexed_version.ReadFromPrefs(local_state_);
+  TRACE_EVENT1(TRACE_DISABLED_BY_DEFAULT("loading"),
+               "RulesetService::RulesetService", "prefs_version",
+               most_recently_indexed_version.ToTracedValue());
   if (most_recently_indexed_version.IsValid() &&
       most_recently_indexed_version.IsCurrentFormatVersion()) {
     OpenAndPublishRuleset(most_recently_indexed_version);

components/subresource_filter/core/browser/ruleset_service.h

@@ -26,6 +26,10 @@ class PrefRegistrySimple;
 
 namespace base {
 class SequencedTaskRunner;
+
+namespace trace_event {
+class TracedValue;
+}  // namespace trace_event
 }  // namespace base
 
 namespace subresource_filter {
@@ -79,6 +83,8 @@ struct IndexedRulesetVersion {
   void SaveToPrefs(PrefService* local_state) const;
   void ReadFromPrefs(PrefService* local_state);
 
+  std::unique_ptr<base::trace_event::TracedValue> ToTracedValue() const;
+
   std::string content_version;
   int format_version = 0;
 };