Revert of [Fallback icons] Change "explicit flow" interface so color hex strings don't use "#".

Revert of [Fallback icons] Change "explicit flow" interface so color hex strings don't use "#". (patchset #4 id:60001 of https://codereview.chromium.org/988863002/)

Reason for revert:
Caused invalid reads on valgrind bots, see https://codereview.chromium.org/988863002/#msg28

Original issue's description:
> [Fallback icons] Change "explicit flow" interface so color hex strings don't use "#".
> 
> Design: go/chrome-fallback-icons
> 
> Fallback icon "explicit flow" URL used to have '#' in hex colors, e.g.:
> 
> chrome://fallback-icon/,#01f,#123456,,/http://www.google.com
> 
> Problem: "#" denotes fragment in URLs, so we get rid of it. This causes no ambiguity
> with named color (e.g., "red") because no named color consists of letters a-f only.
> Also adding "ARGB" hex color since this is supported in Skia color parsing.
> 
> BUG=455063
> 
> Committed: https://crrev.com/8fa91aabefbe9784eca0c169bc2ad2dd92f5d887
> Cr-Commit-Position: refs/heads/master@{#319630}

TBR=jhawkins@chromium.org,huangs@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=455063

[Nico, 2015-03-09 19:42:30]

Created Revert of [Fallback icons] Change "explicit flow" interface so color hex
strings don't use "#".

[commit-bot: I haz the power, 2015-03-09 19:43:05]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/989183003/1

[commit-bot: I haz the power, 2015-03-09 19:44:14]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-03-09 19:44:16]

Failed to apply the patch.

[commit-bot: I haz the power, 2015-03-09 19:45:03]

The CQ bit was unchecked by commit-bot@chromium.org

[huangs, 2015-03-10 04:30:02]

On 2015/03/09 19:44:16, I haz the power (commit-bot) wrote:
> Failed to apply the patch.

Per discussion, the CL has already been reverted by bnc@.  We can close this CL.