All graphs for this bug:
  https://chromeperf.appspot.com/group_report?bug_id=820467

(For debugging:) Original alerts at time of bug-filing:
  https://chromeperf.appspot.com/group_report?sid=7af0df10508cd7c778c6ed13aa1ce07c0ac6b2dbbd370994f0b121b1e2d1b18d


Bot(s) for this bug's original alert(s):

chromium-rel-win7-gpu-nvidia

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/16f23bea440000

📍 Found significant differences after each of 3 commits.
https://pinpoint-dot-chromeperf.appspot.com/job/16f23bea440000

Reland "Add range checks for `StringPiece`." by palmer@chromium.org
https://chromium.googlesource.com/chromium/src/+/e5a6dfada32caaccc93e4f3ca4cb0bd0f6cdd019

[PE] Small optimizations for cc::DisplayItemList by wangxianzhu@chromium.org
https://chromium.googlesource.com/chromium/src/+/bb5d0d6bdb6e29327bce812d1dcd61782001f539

[SPv175] DisplayItem::VisualRect() as FloatRect instead of LayoutRect by wangxianzhu@chromium.org
https://chromium.googlesource.com/chromium/src/+/3cfcee9e2d5e91361d001eae57e430348a33d2a0

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/149b9a96440000

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/134e1232440000

📍 Pinpoint job started.
https://pinpoint-dot-chromeperf.appspot.com/job/174e1232440000

📍 Found a significant difference after 1 commit.
https://pinpoint-dot-chromeperf.appspot.com/job/134e1232440000

[SPv175] DisplayItem::VisualRect() as FloatRect instead of LayoutRect by wangxianzhu@chromium.org
https://chromium.googlesource.com/chromium/src/+/3cfcee9e2d5e91361d001eae57e430348a33d2a0

Understanding performance regressions:
  http://g.co/ChromePerformanceRegressions

 Issue 820471  has been merged into this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0d86ccd6bd11c42c0edb775c806b420f10193f66

commit 0d86ccd6bd11c42c0edb775c806b420f10193f66
Author: Xianzhu Wang <wangxianzhu@chromium.org>
Date: Thu Mar 15 00:52:58 2018

[PE] Optimize FloatRect::EnclosingIntRect() and EnclosedRect()

Use ClampSub on integer values instead of clampTo<int> on float values.

This can improve record time by 3% on Android
(https://pinpoint-dot-chromeperf.appspot.com/job/14d64d9e440000
 click "Analyze benchmark results).

Change-Id: I8521a93caf821c551f342c551b5de84b6e35e092
Bug:  820467 
Reviewed-on: https://chromium-review.googlesource.com/958292
Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543264}
[modify] https://crrev.com/0d86ccd6bd11c42c0edb775c806b420f10193f66/third_party/WebKit/Source/platform/geometry/FloatRect.cpp
[modify] https://crrev.com/0d86ccd6bd11c42c0edb775c806b420f10193f66/third_party/WebKit/Source/platform/geometry/FloatRect.h

SlimmingPaintV175 was enabled after the #c9 CL, and we'll track SPv175 performance instead.

😿 Pinpoint job stopped with an error.
https://pinpoint-dot-chromeperf.appspot.com/job/174e1232440000

😿 Pinpoint job stopped with an error.
https://pinpoint-dot-chromeperf.appspot.com/job/149b9a96440000

Previous job on this bug failed due to https://github.com/catapult-project/catapult/issues/4393, retrying now that it's fixed.

📍 Pinpoint job started.
https://chromeperf.appspot.com/job/14f014aac40000