binding: Updates Jinja2 from 2.7.1 to 2.8.

New feature in 2.8:
- block assignment
  {% set var_name %} content {% endset %}

Manually edited files:
  README.chromium
  get_jinja2.sh

BUG=

Review-Url: https://codereview.chromium.org/2316103002
Cr-Commit-Position: refs/heads/master@{#417191}


CrOS-Libchrome-Original-Commit: a34bd686422a4af68b566c2d045b978524bd2cbf
24 files changed
tree: c94a214a807078b4105af2e7c9a46a5076744ce0
  1. base/
  2. build/
  3. components/
  4. dbus/
  5. device/
  6. ipc/
  7. mojo/
  8. testing/
  9. third_party/
  10. ui/