Revert "[DevTools] Disable contrast information in inspect tooltip"

This reverts commit 568f3235767392764ddb1082f7d7b285b7e4164f.

Reason for revert: there is a better fix, uploading shortly.

Original change's description:
> [DevTools] Disable contrast information in inspect tooltip
> 
> Calculating contrast ratio has performance issues on large DOMs.
> Disabling until further investigation to not regress existing users.
> 
> Bug: 951817
> Change-Id: I564e0b42d84771d61e58488412e96969a3326294
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1570646
> Reviewed-by: Erik Luo <luoe@chromium.org>
> Commit-Queue: Dmitry Gozman <dgozman@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#651482}

TBR=dgozman@chromium.org,luoe@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 951817
Change-Id: Ie377f84793a00b6d139380d94d37d74987379b91
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1577866
Reviewed-by: Pavel Feldman OOO <pfeldman@chromium.org>
Commit-Queue: Pavel Feldman OOO <pfeldman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653053}
1 file changed