commit 6fee454f21e59fed7415b692a542af225fd27d33
author Yuri Wiitala <miu@chromium.org> Mon Dec 10 10:51:54 2018
committer Commit Bot <commit-bot@chromium.org> Mon Dec 10 10:51:54 2018
tree 5032f67b176153ab42465fc9629e35334ce72e22
parent d20372bed4393fc15612798427847dd7c9a7d1b0

Make ChromeDriver.testTakeElementScreenshot() color space friendly.

Uses the web engine itself to sanity-check the element snapshot PNG,
rather than doing an exact binary comparison of an expected PNG file's
content. This will unblock a soon-upcoming change where the screen
capture pipeline will become color space aware, and so the PNG file from
the snapshot API will start including different color space metadata
(even though its pixel values will be exactly the same).

An extra benefit to testing this way is that more of the browser will
be tested for color space awareness/correctness (i.e., its PNG image
decoder, and HTML Canvas drawing and readback).

Bug: 758057
Change-Id: Ibde9a18fe6b70b5c6532e1f888f8db2c4549eb9b
Reviewed-on: https://chromium-review.googlesource.com/c/1369037
Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Yuri Wiitala <miu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615078}