The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/54aa2e86754b30b0681f4ca4f84f709f28a6851f

commit 54aa2e86754b30b0681f4ca4f84f709f28a6851f
Author: Ian Clelland <iclelland@chromium.org>
Date: Thu May 03 17:42:31 2018

Add legacy-image-formats and image-compression policies

These policies are intended to allow developers to control which image
formats are supported on their pages (and on the pages they embed,) and
to enforce that images used are well compressed and not full of
metadata which does not contribute to the displayed image.

Explainers for these features can be found at
https://github.com/WICG/feature-policy/blob/gh-pages/policies/optimized-images.md

Bug:  837348 ,  837350 
Change-Id: Ie92517291a453286ca0d745f8dc497f040c06592
Reviewed-on: https://chromium-review.googlesource.com/1033726
Reviewed-by: Nate Chapin <japhet@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Commit-Queue: Ian Clelland <iclelland@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555795}
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/feature-policy-image-compression-expected.png
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/feature-policy-image-compression-expected.txt
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/feature-policy-image-compression.html
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/feature-policy-legacy-formats-expected.png
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/feature-policy-legacy-formats-expected.txt
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/feature-policy-legacy-formats.html
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/resources/Fisher-large.jpg
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/resources/Fisher-small.jpg
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/resources/Fisher.bmp
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/resources/frame-with-compression-test-images.html
[add] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/WebKit/LayoutTests/http/tests/images/resources/frame-with-legacy-image.html
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/common/feature_policy/feature_policy.cc
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/public/mojom/feature_policy/feature_policy.mojom
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/renderer/core/html/html_image_loader.cc
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/renderer/core/loader/resource/image_resource_content.cc
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/renderer/core/loader/resource/image_resource_content.h
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/renderer/platform/feature_policy/feature_policy.cc
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/renderer/platform/network/mime/mime_type_registry.cc
[modify] https://crrev.com/54aa2e86754b30b0681f4ca4f84f709f28a6851f/third_party/blink/renderer/platform/network/mime/mime_type_registry.h