Revert "SVGLength.value setter should set the value to <number>"

This reverts r403440 (commit c825d655f6aaf73484f9d56e9012793f5b9668cc),
as it caused a security regression.

BUG=626790
TBR=shanmuga.m@samsung.com

Review-Url: https://codereview.chromium.org/2147003002
Cr-Commit-Position: refs/heads/master@{#405264}
4 files changed