[DevTools] Evaluate expression like { ... } as Object Literal

If user evaluate in console expression like {a:1, b:2} then console will report SyntaxError exception because this expression is interpreted as block scope declaration with incorrect label.
With this CL console wrap all expressions that begins with { and ends with }.

BUG=499864
R=paulirish@chromium.org, pfeldman@chromium.org

Review URL: https://codereview.chromium.org/1511043002

Cr-Commit-Position: refs/heads/master@{#364270}
3 files changed