Moving this nonessential bug to the next milestone.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/72b7454b7d1ea60317365a076187da54e646e88e

commit 72b7454b7d1ea60317365a076187da54e646e88e
Author: sclittle <sclittle@chromium.org>
Date: Mon Oct 24 20:49:06 2016

Add Blink support for showing image placeholders using range requests.

Design doc:
https://docs.google.com/document/d/1691W7yFDI1FJv69N2MEtaSzpnqO2EqkgGD3T0O-pQ08/edit?usp=sharing

This CL introduces support for issuing a range request for just the
first few bytes of an image, and showing a translucent gray box of the
same size as the image in the image's place if the original image's
dimensions can be decoded from the returned range.

Currently, this behavior is only activated via a blink-settings flag. In
the future, features such as Data Saver will activate this functionality
to save data for users.

BUG= 605350 , 605351 

Review-Url: https://codereview.chromium.org/2423683002
Cr-Commit-Position: refs/heads/master@{#427141}

[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/css/CSSImageSetValue.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/css/CSSImageValue.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/FetchRequest.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/FetchRequest.h
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/ImageResource.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/ImageResource.h
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/ImageResourceTest.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/Resource.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/Resource.h
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/frame/Settings.in
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/loader/DocumentLoader.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/loader/ImageLoader.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/loader/ProgressTracker.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/core/page/DragController.cpp
[modify] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/platform/BUILD.gn
[add] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/platform/graphics/PlaceholderImage.cpp
[add] https://crrev.com/72b7454b7d1ea60317365a076187da54e646e88e/third_party/WebKit/Source/platform/graphics/PlaceholderImage.h