cc: Add SwapAck watchdog.

cc/scheduler/scheduler_settings.cc

Index: cc/scheduler/scheduler_settings.cc
diff --git a/cc/scheduler/scheduler_settings.cc b/cc/scheduler/scheduler_settings.cc
index 6f174fa1ba9c6f5a34a119bcb4332c1dce0fc10a..e828510df9d90c4a30a010ad21d011abe5c48aa9 100644
--- a/cc/scheduler/scheduler_settings.cc
+++ b/cc/scheduler/scheduler_settings.cc
@@ -18,7 +18,8 @@ SchedulerSettings::SchedulerSettings()
       throttle_frame_production(true),
       abort_commit_before_output_surface_creation(true),
       maximum_number_of_failed_draws_before_draw_is_forced(3),
-      background_frame_interval(base::TimeDelta::FromSeconds(1)) {}
+      background_frame_interval(base::TimeDelta::FromSeconds(1)),
+      swap_ack_watchdog_enabled(false) {}
 
 SchedulerSettings::SchedulerSettings(const SchedulerSettings& other) = default;
 
@@ -46,6 +47,7 @@ SchedulerSettings::AsValue() const {
                     background_frame_interval.InMicroseconds());
   state->SetBoolean("abort_commit_before_output_surface_creation",
                     abort_commit_before_output_surface_creation);
+  state->SetBoolean("swap_ack_watchdog_enabled", swap_ack_watchdog_enabled);
   return std::move(state);
 }