Adding CPEPrefixes for more dependencies.

Adding CPEPrefix lines which will allow Vomit to report crbugs for known
vulnerabilities in these components.

See
docs/adding_to_third_party.md
for information about CPEPrefix.

Notes about how some of these were figured out:

* libxml: deduced by looking through the history from the git hash
  given in the latest git commit.
* fontconfig: Went through git history to last tag; matches README
* jsoncpp: Used latest tag.
* Flash is marked as 'unknown', since it's not the real Flash player.
* The Camino Cocoa extensions don't have a corresponding OSS project
  any longer so are also marked as 'unknown'.

Bug: 895969
Change-Id: Iadcd9fff258c18d759d564f15fe4fa334c98b441
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2128971
Reviewed-by: Raymes Khoury <raymes@chromium.org>
Reviewed-by: Charlie Reis <creis@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Commit-Queue: Adrian Taylor <adetaylor@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#756146}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 2dde69963e33e8560ee7dab6b309bd5c4f4cf444
diff --git a/README.chromium b/README.chromium
index 5246c2f..9b8311a 100644
--- a/README.chromium
+++ b/README.chromium
@@ -2,6 +2,7 @@
 Short Name: jinja2
 URL: http://jinja.pocoo.org/
 Version: 2.10
+CPEPrefix: cpe:/a:pocoo:jinja2:2.10
 License: BSD 3-Clause
 License File: LICENSE
 Security Critical: no