Use less conservative condition when detecting noncharacter unicode symbols
Use less conservative condition when detecting noncharacter unicode symbols

All noncharacter code points are >= 0xD800 so we can use more liberal condition when detecing characters that needs to be esscaped.

BUG=347899

Review URL: https://codereview.chromium.org/180113008

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@168547 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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