[tracing] Add trace events filtering predicate for heap profiler

base/trace_event/trace_log_constants.cc

Index: base/trace_event/trace_log_constants.cc
diff --git a/base/trace_event/trace_log_constants.cc b/base/trace_event/trace_log_constants.cc
index cd2ff0dad3fb87c76d1a175baabe69a88e15ca02..9d4fe07f0d6d2545e22490d6d908f81aefd9183b 100644
--- a/base/trace_event/trace_log_constants.cc
+++ b/base/trace_event/trace_log_constants.cc
@@ -23,5 +23,11 @@ const TraceLog::InternalTraceOptions
 const TraceLog::InternalTraceOptions
     TraceLog::kInternalEnableArgumentFilter = 1 << 5;
 
+// TraceEventFilter predicate names used in trace config.
+const char* const TraceLog::TraceEventFilter::kEventWhitelistPredicate =
+    "event_whitelist_predicate";
+const char* const TraceLog::TraceEventFilter::kHeapProfilerPredicate =
+    "heap_profiler_predicate";
+
 }  // namespace trace_event
 }  // namespace base