Define EnumTraits for many IndexedDB enums.

third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h

Index: third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h
diff --git a/third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h b/third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h
index 6d6a00de3b9bf2cd4cbfabbffdfc140596918f9b..76602efd7ec103e9860b62a67833f487225d5426 100644
--- a/third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h
+++ b/third_party/WebKit/public/platform/modules/indexeddb/WebIDBTypes.h
@@ -55,20 +55,17 @@ enum WebIDBCursorDirection {
   WebIDBCursorDirectionNextNoDuplicate = 1,
   WebIDBCursorDirectionPrev = 2,
   WebIDBCursorDirectionPrevNoDuplicate = 3,
-  WebIDBCursorDirectionLast = WebIDBCursorDirectionPrevNoDuplicate
 };
 
 enum WebIDBTaskType {
   WebIDBTaskTypeNormal = 0,
   WebIDBTaskTypePreemptive,
-  WebIDBTaskTypeLast = WebIDBTaskTypePreemptive
 };
 
 enum WebIDBPutMode {
   WebIDBPutModeAddOrUpdate,
   WebIDBPutModeAddOnly,
   WebIDBPutModeCursorUpdate,
-  WebIDBPutModeLast = WebIDBPutModeCursorUpdate
 };
 
 enum WebIDBOperationType {
@@ -84,7 +81,6 @@ enum WebIDBTransactionMode {
   WebIDBTransactionModeReadOnly = 0,
   WebIDBTransactionModeReadWrite,
   WebIDBTransactionModeVersionChange,
-  WebIDBTransactionModeLast = WebIDBTransactionModeVersionChange
 };
 
 }  // namespace blink