sync: Remove session member from SyncSessionJob

This change removes the SyncSession member of SyncSessionJob.  The
session had two very important responsibilities:
1. Tracking the source and notification hints for the current job.
2. Indicating whether or not a job had been abandoned.

We now track the source of a job directly in SyncSessionJob.  The
debug_info_sources_list has been removed entirely.  The investigation
that triggered its addition has been put on hold for now and it is
unliekly we will need this information in the future.

Tracking abandoned jobs is a bit more difficult.  The scheduler used to
keep track of SyncSessions very carefully, since only a valid session
would allow a job to actually proceed.

This patch introduces a new approach for limiting the number of pending
jobs.  The scheduler now maintains a single scoped_ptr to a
CancelableClosure.  All scheduled tasks will be wrapped in a
CancelableClosure that will be owned by this scoped_ptr.  If a new task
pre-empts an existing task, it will overwrite the scoped_ptr, which will
prevent the old task from running.  Therefore, only one task may be
pending at any given time.  This should help prevent issues like
crbug.com/139723, though it also introduces new failure modes.

BUG=175024


Review URL: https://chromiumcodereview.appspot.com/12942005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@191458 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 1 insertions, 25 deletions

diff --git a/sync/internal_api/public/sessions/sync_session_snapshot.cc b/sync/internal_api/public/sessions/sync_session_snapshot.cc
index b0e9fac..8c0c2b9 100644
--- a/sync/internal_api/public/sessions/sync_session_snapshot.cc
+++ b/sync/internal_api/public/sessions/sync_session_snapshot.cc
@@ -31,7 +31,6 @@ 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,
@@ -44,7 +43,6 @@ 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),
@@ -86,13 +84,6 @@ 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());
@@ -147,11 +138,6 @@ 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 be29d35..3e1c20e 100644
--- a/sync/internal_api/public/sessions/sync_session_snapshot.h
+++ b/sync/internal_api/public/sessions/sync_session_snapshot.h
@@ -38,7 +38,6 @@ class SYNC_EXPORT 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,
@@ -61,7 +60,6 @@ class SYNC_EXPORT 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;
@@ -79,7 +77,6 @@ class SYNC_EXPORT 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 9301ffd..1d9f198 100644
--- a/sync/internal_api/public/sessions/sync_session_snapshot_unittest.cc
+++ b/sync/internal_api/public/sessions/sync_session_snapshot_unittest.cc
@@ -47,11 +47,6 @@ 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,
                                download_progress_markers,
                                kIsSilenced,
@@ -59,14 +54,13 @@ 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(18u, value->size());
+  EXPECT_EQ(17u, value->size());
   ExpectDictIntegerValue(model_neutral.num_successful_commits,
                          *value, "numSuccessfulCommits");
   ExpectDictIntegerValue(model_neutral.num_successful_bookmark_commits,
@@ -93,7 +87,6 @@ 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");
 }