android_webview: Enable ProGuard obfusction

Bug: 855726
Change-Id: I451b9cc0d68982a9cf3deba0af3d7146e8beb14b
Reviewed-on: https://chromium-review.googlesource.com/1114348
Reviewed-by: Richard Coles <torne@chromium.org>
Reviewed-by: Nate Fischer <ntfschr@chromium.org>
Commit-Queue: agrieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#577573}
3 files changed