Looks like this is related to the "exact" code-path of Path::boundingRect (TightBounds in Skia.)

Looks like the TightBounds inverse-scale the path, but does not scale the computed bounds to compensate.

The following revision refers to this bug:
  https://skia.googlesource.com/skia.git/+/b60e8645ecddb1846cdba52073db394a633841ff

commit b60e8645ecddb1846cdba52073db394a633841ff
Author: Fredrik Söderquist <fs@opera.com>
Date: Wed Jan 04 12:31:47 2017

Scale the result of TightBounds when path was inverse-scaled

When the path was "large" (as defined by ScaleFactor(...)), the computed
bounds would not be adjusted to the correct space. Make sure to scale
the result in those cases.

BUG= chromium:678162 

Change-Id: Ia2eb94050c4620286e9abb69976dbc0202ecc307
Reviewed-on: https://skia-review.googlesource.com/6501
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>

[modify] https://crrev.com/b60e8645ecddb1846cdba52073db394a633841ff/src/pathops/SkPathOpsTightBounds.cpp
[modify] https://crrev.com/b60e8645ecddb1846cdba52073db394a633841ff/tests/PathOpsTightBoundsTest.cpp

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c540247a6240219871357c5c9f310d90f0cb4a48

commit c540247a6240219871357c5c9f310d90f0cb4a48
Author: skia-deps-roller <skia-deps-roller@chromium.org>
Date: Wed Jan 04 16:57:13 2017

Roll src/third_party/skia/ 671163843..2be687af5 (5 commits).

https://skia.googlesource.com/skia.git/+log/671163843681..2be687af58ec

$ git log 671163843..2be687af5 --date=short --no-merges --format='%ad %ae %s'
2017-01-03 ethannicholas fix skslc crash when ternary parameter types don't match
2017-01-04 msarett Use shared toSRGBD50 matrix in SkPngCodec
2017-01-03 bungeman Stage SkFontMgr factories to return smart pointers.
2017-01-03 mtklein Remove SkImageShader -> SkColorShader optimization.
2017-01-04 fs Scale the result of TightBounds when path was inverse-scaled

BUG= 678162 

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel
TBR=csmartdalton@google.com

Review-Url: https://codereview.chromium.org/2611873003
Cr-Commit-Position: refs/heads/master@{#441398}

[modify] https://crrev.com/c540247a6240219871357c5c9f310d90f0cb4a48/DEPS