[Sync] Record sync memory usage in histogram broken by datatypes

components/sync/model/model_type_debug_info.cc

Index: components/sync/model/model_type_debug_info.cc
diff --git a/components/sync/model/model_type_debug_info.cc b/components/sync/model/model_type_debug_info.cc
index f2f1dfdd09d9575b4855a6429a4ecbac136a67c8..0d1f6e3e3fb8b9cd8e12235d096e9b40fb87f14e 100644
--- a/components/sync/model/model_type_debug_info.cc
+++ b/components/sync/model/model_type_debug_info.cc
@@ -9,6 +9,7 @@
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
+#include "components/sync/base/data_type_histogram.h"
 #include "components/sync/model_impl/processor_entity_tracker.h"
 #include "components/sync/protocol/proto_value_conversions.h"
 
@@ -59,6 +60,15 @@ void ModelTypeDebugInfo::GetStatusCounters(
   }
 }
 
+// static
+void ModelTypeDebugInfo::RecordMemoryUsageHistogram(
+    ModelTypeSyncBridge* bridge) {
+  SharedModelTypeProcessor* processor = GetProcessorFromBridge(bridge);
+  size_t memory_usage = processor->EstimateMemoryUsage();
+  SyncRecordMemoryKbHistogram("Sync.ModelTypeMemoryKB.", processor->type_,
+                              memory_usage / 1024);
+}
+
 ModelTypeDebugInfo::ModelTypeDebugInfo() {}
 
 // static