Using the per-revision bisect providing the bisect results,
Good Build -- 58.0.3012.0 (revision : 450199)
Bad Build  -- 58.0.3013.0 (revision : 450530)

You are probably looking for a change made after 450369 (known good), but no later than 450370 (first known bad).
CHANGELOG URL:
  https://chromium.googlesource.com/chromium/src/+log/18375370aff250f59f5ef624ecf686d860377ece..d892f9592860691ae9a782c12260c94ed6bd1a63

@yosin -- Could you please look into the issue, kindly re-assign if this is not related to your changes.
Adding RB Label as this is a recent Regression, please remove if not required.
Thank You.

Step to reproduce:
1. Visit http://textarea.org
2. See the page, caret is blinking
3. Type "x" or whatever key

 Issue 692989  has been merged into this issue.

The root cause is we stop caret blink timer when last editing command is typing in
FrameCaret::updateApperance(). Before patch[1], updateApperance() is called when
selection is moved. But after patch[1], we call updateApperance() before
painting caret.

Able to reproduce this issue on Mac 10.12.3 with chrome dev #58.0.3024.0, 
yosin@ since it has a release block-stable label , could you please provide the latest update on this issue.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/045a3dd143fabf6787774090a255dc0eda649c59

commit 045a3dd143fabf6787774090a255dc0eda649c59
Author: tkent <tkent@chromium.org>
Date: Wed Mar 01 05:55:00 2017

Editing: Fix caret blinking after a typing.

FrameCaret::updateAppearance() is called in updateStyleAndLayoutIfNeeded(). So
if shouldStopBlinkingDueToTypingCommand() is true, we repeatedly stop and start
the caret timer.

Because FrameSelection::didSetSelectionDeprecated() calls stopCaretBlinkTimer(),
we always restart the caret timer after every selection change. Checking
shouldStopBlinkingDueToTypingCommand() is unnecessary.

The core part of the CL is just to remove
shouldStopBlinkingDueToTypingCommand(), however this CL adds a lot of code to
make the code testable.
- Add FrameCaret::recreateCaretBlinkTimerForTesting(RefPtr<WebTaskRunner>)
- Add FrameSelection::frameCaretForTesting()
- Add support of delayed task to FakeWebTaskRunner

BUG= 692900 

Review-Url: https://codereview.chromium.org/2723003002
Cr-Commit-Position: refs/heads/master@{#453858}

[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/BUILD.gn
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/FrameCaret.cpp
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/FrameCaret.h
[add] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/FrameCaretTest.cpp
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/FrameSelection.h
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/commands/CompositeEditCommand.h
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/core/editing/commands/TypingCommand.h
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/platform/WebTaskRunnerTest.cpp
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/platform/scheduler/test/fake_web_task_runner.cc
[modify] https://crrev.com/045a3dd143fabf6787774090a255dc0eda649c59/third_party/WebKit/Source/platform/scheduler/test/fake_web_task_runner.h

Issue 696018 has been merged into this issue.

Tested the issue on Latest Dev# 58.0.3029.6 on Windows, Mac and Linux and found the issue to be Fixed.
Blinking doesn't stop on hitting backspace. Hence adding TE-Verified Labels.
Attaching Screencast for reference.
Thank You.

Deleted: 692900.ogv 1.7 MB

	692900.ogv 1.7 MB View Download