Track merged nudge sources

There's a lot of valuable information in coalesced nudges.  Currently, one
nudge source can overwrite another, which leaves us in the dark as to why the
client behaved a certain way.  In fact, today we can't even determine whether
or not any coalescing was done.  

By logging all the coalesced sources and their payloads, we can learn a lot
more about client behaviour.  I'm hoping to use this to improve our
notification effectiveness metrics.

BUG=138613

Review URL: https://chromiumcodereview.appspot.com/11416126

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@170549 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 25 insertions, 2 deletions

diff --git a/sync/internal_api/public/sessions/sync_session_snapshot.cc b/sync/internal_api/public/sessions/sync_session_snapshot.cc
index 5e25da3..d74ffa7 100644
--- a/sync/internal_api/public/sessions/sync_session_snapshot.cc
+++ b/sync/internal_api/public/sessions/sync_session_snapshot.cc
@@ -34,6 +34,7 @@ SyncSessionSnapshot::SyncSessionSnapshot(
     int num_hierarchy_conflicts,
     int num_server_conflicts,
     const SyncSourceInfo& source,
+    const std::vector<SyncSourceInfo>& debug_info_sources_list,
     bool notifications_enabled,
     size_t num_entries,
     base::Time sync_start_time,
@@ -48,6 +49,7 @@ SyncSessionSnapshot::SyncSessionSnapshot(
       num_hierarchy_conflicts_(num_hierarchy_conflicts),
       num_server_conflicts_(num_server_conflicts),
       source_(source),
+      debug_info_sources_list_(debug_info_sources_list),
       notifications_enabled_(notifications_enabled),
       num_entries_(num_entries),
       sync_start_time_(sync_start_time),
@@ -92,9 +94,15 @@ DictionaryValue* SyncSessionSnapshot::ToValue() const {
                     num_server_conflicts_);
   value->SetInteger("numEntries", num_entries_);
   value->Set("source", source_.ToValue());
+  scoped_ptr<ListValue> sources_list(new ListValue());
+  for (std::vector<SyncSourceInfo>::const_iterator i =
+       debug_info_sources_list_.begin();
+       i != debug_info_sources_list_.end(); ++i) {
+    sources_list->Append(i->ToValue());
+  }
+  value->Set("sourcesList", sources_list.release());
   value->SetBoolean("notificationsEnabled", notifications_enabled_);
 
-
   scoped_ptr<DictionaryValue> counter_entries(new DictionaryValue());
   for (int i = FIRST_REAL_MODEL_TYPE; i < MODEL_TYPE_COUNT; i++) {
     scoped_ptr<DictionaryValue> type_entries(new DictionaryValue());
@@ -155,6 +163,11 @@ SyncSourceInfo SyncSessionSnapshot::source() const {
   return source_;
 }
 
+const std::vector<SyncSourceInfo>&
+SyncSessionSnapshot::debug_info_sources_list() const {
+  return debug_info_sources_list_;
+}
+
 bool SyncSessionSnapshot::notifications_enabled() const {
   return notifications_enabled_;
 }
diff --git a/sync/internal_api/public/sessions/sync_session_snapshot.h b/sync/internal_api/public/sessions/sync_session_snapshot.h
index c6b3c78..8252419 100644
--- a/sync/internal_api/public/sessions/sync_session_snapshot.h
+++ b/sync/internal_api/public/sessions/sync_session_snapshot.h
@@ -39,6 +39,7 @@ class SyncSessionSnapshot {
       int num_hierarchy_conflicts,
       int num_server_conflicts,
       const SyncSourceInfo& source,
+      const std::vector<SyncSourceInfo>& debug_info_sources_list,
       bool notifications_enabled,
       size_t num_entries,
       base::Time sync_start_time,
@@ -63,6 +64,7 @@ class SyncSessionSnapshot {
   int num_hierarchy_conflicts() const;
   int num_server_conflicts() const;
   SyncSourceInfo source() const;
+  const std::vector<SyncSourceInfo>& debug_info_sources_list() const;
   bool notifications_enabled() const;
   size_t num_entries() const;
   base::Time sync_start_time() const;
@@ -82,6 +84,7 @@ class SyncSessionSnapshot {
   int num_hierarchy_conflicts_;
   int num_server_conflicts_;
   SyncSourceInfo source_;
+  std::vector<SyncSourceInfo> debug_info_sources_list_;
   bool notifications_enabled_;
   size_t num_entries_;
   base::Time sync_start_time_;
diff --git a/sync/internal_api/public/sessions/sync_session_snapshot_unittest.cc b/sync/internal_api/public/sessions/sync_session_snapshot_unittest.cc
index df33a41..5a97a16 100644
--- a/sync/internal_api/public/sessions/sync_session_snapshot_unittest.cc
+++ b/sync/internal_api/public/sessions/sync_session_snapshot_unittest.cc
@@ -53,6 +53,11 @@ TEST_F(SyncSessionSnapshotTest, SyncSessionSnapshotToValue) {
   SyncSourceInfo source;
   scoped_ptr<DictionaryValue> expected_source_value(source.ToValue());
 
+  std::vector<SyncSourceInfo> debug_info_sources_list;
+  debug_info_sources_list.push_back(source);
+  scoped_ptr<ListValue> expected_sources_list_value(new ListValue());
+  expected_sources_list_value->Append(source.ToValue());
+
   SyncSessionSnapshot snapshot(model_neutral,
                                kIsShareUsable,
                                initial_sync_ended,
@@ -62,13 +67,14 @@ TEST_F(SyncSessionSnapshotTest, SyncSessionSnapshotToValue) {
                                kNumHierarchyConflicts,
                                kNumServerConflicts,
                                source,
+                               debug_info_sources_list,
                                false,
                                0,
                                base::Time::Now(),
                                std::vector<int>(MODEL_TYPE_COUNT,0),
                                std::vector<int>(MODEL_TYPE_COUNT, 0));
   scoped_ptr<DictionaryValue> value(snapshot.ToValue());
-  EXPECT_EQ(19u, value->size());
+  EXPECT_EQ(20u, value->size());
   ExpectDictIntegerValue(model_neutral.num_successful_commits,
                          *value, "numSuccessfulCommits");
   ExpectDictIntegerValue(model_neutral.num_successful_bookmark_commits,
@@ -98,6 +104,7 @@ TEST_F(SyncSessionSnapshotTest, SyncSessionSnapshotToValue) {
   ExpectDictIntegerValue(kNumServerConflicts, *value,
                          "numServerConflicts");
   ExpectDictDictionaryValue(*expected_source_value, *value, "source");
+  ExpectDictListValue(*expected_sources_list_value, *value, "sourcesList");
   ExpectDictBooleanValue(false, *value, "notificationsEnabled");
 }