IndexedDB: Avoid side effects for array key conversion w/ HasOwnProperty

third_party/WebKit/Source/bindings/modules/v8/V8BindingForModules.cpp

Index: third_party/WebKit/Source/bindings/modules/v8/V8BindingForModules.cpp
diff --git a/third_party/WebKit/Source/bindings/modules/v8/V8BindingForModules.cpp b/third_party/WebKit/Source/bindings/modules/v8/V8BindingForModules.cpp
index 098a4180c05a7ff283381be8899540340aea9b0e..264029b612221e3ad8821e86929eb78530b73ea4 100644
--- a/third_party/WebKit/Source/bindings/modules/v8/V8BindingForModules.cpp
+++ b/third_party/WebKit/Source/bindings/modules/v8/V8BindingForModules.cpp
@@ -213,9 +213,12 @@ static IDBKey* createIDBKeyFromValue(v8::Isolate* isolate, v8::Local<v8::Value>
         IDBKey::KeyArray subkeys;
         uint32_t length = array->Length();
         v8::TryCatch block(isolate);
+        v8::Local<v8::Context> context = isolate->GetCurrentContext();
         for (uint32_t i = 0; i < length; ++i) {
+            if (!v8CallBoolean(array->HasOwnProperty(context, i)))
+                return nullptr;
             v8::Local<v8::Value> item;
-            if (!v8Call(array->Get(isolate->GetCurrentContext(), i), item, block)) {
+            if (!v8Call(array->Get(context, i), item, block)) {
                 exceptionState.rethrowV8Exception(block.Exception());
                 return nullptr;
             }