In DevTools we've already used sourceURL in inline scripts.
This CL makes the behavior of the V8 in the same for Error.stack property and v8::StackTrace.

BUG=v8:3920
LOG=Y
R=yangguo@chromium.org

Review URL: https://codereview.chromium.org/1044173002

Cr-Commit-Position: refs/heads/master@{#27554}