The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5028f29b34a25f0b28e11e9a2185918439f77829

commit 5028f29b34a25f0b28e11e9a2185918439f77829
Author: Dominik Röttsches <drott@chromium.org>
Date: Thu Oct 26 10:27:20 2017

Update FontSelectionAlgorithm for weights between 400 and 500

The CSS WG updated the font selection algorithm's behavior for weight
ranges between 400 and 500 to allow for smooth animations. [1]

[1] https://github.com/w3c/csswg-drafts/commit/f6973a21847f1c200ed38bff05dc543cebe1c827

Test: Added WidthRangeMatchingBetween400500 to FontFaceCacheTest
Bug:  777441 
Change-Id: If9bb55bb02ce4148793531fd8ebe11bae98eb83f
Reviewed-on: https://chromium-review.googlesource.com/738130
Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Dominik Röttsches <drott@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511784}
[modify] https://crrev.com/5028f29b34a25f0b28e11e9a2185918439f77829/third_party/WebKit/Source/core/css/FontFaceCacheTest.cpp
[modify] https://crrev.com/5028f29b34a25f0b28e11e9a2185918439f77829/third_party/WebKit/Source/platform/fonts/FontSelectionAlgorithm.cpp
[modify] https://crrev.com/5028f29b34a25f0b28e11e9a2185918439f77829/third_party/WebKit/Source/platform/fonts/FontSelectionTypes.h