IndexedDB: add ENABLE_LEVELDB=1 to features_override.gypi

TEST=none
BUG=64078

Review URL: http://codereview.chromium.org/6824077

git-svn-id: http://src.chromium.org/svn/trunk/src/build@81248 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

features_override.gypi

@@ -34,6 +34,7 @@
       'ENABLE_INPUT_SPEECH=1',
       'ENABLE_JAVASCRIPT_DEBUGGER=1',
       'ENABLE_JSC_MULTIPLE_THREADS=0',
+      'ENABLE_LEVELDB=1',
       'ENABLE_LINK_PREFETCH=1',
       'ENABLE_METER_TAG=1',
       'ENABLE_MEDIA_STATISTICS=1',