The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9261f26075fab250385db2abde6c63deec1961ed

commit 9261f26075fab250385db2abde6c63deec1961ed
Author: robhogan <robhogan@gmail.com>
Date: Thu Jun 01 06:43:30 2017

Update our treatment of repeating headers in tables

https://drafts.csswg.org/css-tables-3/#repeated-headers has been updated since
we first implemented them. Respect the new rules such as only repeating headers
if they fit on at most a quarter of the page. We also need to repeat headers
even if only part of a row fits on the page - respecting this rule requires us
to reintroduce allowing nested repeated headers, something that both Edge and
FF do and which is now supported by the spec.

BUG= 720620 ,  675904 

CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2882043002
Cr-Commit-Position: refs/heads/master@{#476212}

[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fast/multicol/balance-repeating-table-headers.html
[add] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-cell-repeating-thead-break-inside-avoid-content-expected.html
[add] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-cell-repeating-thead-break-inside-avoid-content.html
[add] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-cell-repeating-thead-break-inside-content-expected.html
[add] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-cell-repeating-thead-break-inside-content-first-line-expected.html
[add] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-cell-repeating-thead-break-inside-content-first-line.html
[add] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-cell-repeating-thead-break-inside-content.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-large-cell-with-header-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-large-cell-with-header.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-nested-repeating-thead-2-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-nested-repeating-thead-3-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-nested-repeating-thead-4-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-nested-repeating-thead-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-2-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-2.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-3-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-3.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-starts-middle-of-page-break-after-avoid-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-with-border-spacing-at-top-of-row-expected.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/LayoutTests/fragmentation/single-line-cells-repeating-thead-with-border-spacing-at-top-of-row.html
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutBox.cpp
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutState.cpp
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutState.h
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutTable.cpp
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutTableRow.cpp
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutTableRow.h
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutTableSection.cpp
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/layout/LayoutTableSection.h
[modify] https://crrev.com/9261f26075fab250385db2abde6c63deec1961ed/third_party/WebKit/Source/core/paint/TableSectionPainter.cpp

The bug is marked as P3 or Feature. It should not be merged as M60 is in beta. 
Please contact the approriate milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), josafat@(ChromeOS), bustamante@(Desktop)

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