[tracing] Whitelist sync MDP.

base/trace_event/memory_infra_background_whitelist.cc

Index: base/trace_event/memory_infra_background_whitelist.cc
diff --git a/base/trace_event/memory_infra_background_whitelist.cc b/base/trace_event/memory_infra_background_whitelist.cc
index 21bff6904568bd0bd13af4078ea3e2363fcd887f..c8ba4ed8c84efd6f8dede230583801c1049d2892 100644
--- a/base/trace_event/memory_infra_background_whitelist.cc
+++ b/base/trace_event/memory_infra_background_whitelist.cc
@@ -34,6 +34,7 @@ const char* const kDumpProviderWhitelist[] = {
     "Sql",
     "V8Isolate",
     "WinHeap",
+    "SyncDirectory",
     nullptr  // End of list marker.
 };
 
@@ -91,6 +92,8 @@ const char* const kAllocatorDumpNameWhitelist[] = {
     "v8/isolate_0x?/zapped_for_debug",
     "winheap",
     "winheap/allocated_objects",
+    "sync/0x?/kernel",
+    "sync/0x?/store",
     nullptr  // End of list marker.
 };