[IndexedDB] Adding txn, value, and key size metrics

third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 477 matching lines @@
   HeapVector<IndexKeys> index_keys;
   for (const auto& it : Metadata().indexes) {
     if (clone.IsEmpty())
       value_wrapper.Clone(script_state, &clone);
     IndexKeys keys;
     GenerateIndexKeysForValue(script_state->GetIsolate(), *it.value, clone,
                               &keys);
     index_ids.push_back(it.key);
     index_keys.push_back(keys);
   }
+  UMA_HISTOGRAM_MEMORY_KB("WebCore.IndexedDB.PutValueSize",
+                          value_wrapper.DataLengthBeforeWrapInBytes() / 1024);
 
   IDBRequest* request =
       IDBRequest::Create(script_state, source, transaction_.Get());
 
   value_wrapper.ExtractBlobDataHandles(request->transit_blob_handles());
   value_wrapper.WrapIfBiggerThan(IDBValueWrapper::kWrapThreshold);
 
   BackendDB()->Put(
       transaction_->Id(), Id(), WebData(value_wrapper.ExtractWireBytes()),
       value_wrapper.WrappedBlobInfo(), key,
@@ skipping 542 matching lines @@
     }
   }
   return IDBIndexMetadata::kInvalidId;
 }
 
 WebIDBDatabase* IDBObjectStore::BackendDB() const {
   return transaction_->BackendDB();
 }
 
 }  // namespace blink