It seems that InputMethodService#onUpdateSelection() is called with wrong arguments unexpectedly.

If you are on http://www.google.co.jp/ and input a character, #onUpdateSelection() is called with the followings.
(a1) oldSelStart:0, oldSelEnd:24, newSelStart:1, newSelEnd:1, candStart:0, candEnd:1

On the other hand, if you are on http://pc.watch.impress.co.jp/,
(b1) oldSelStart:0, oldSelEnd:22, newSelStart:22, newSelEnd:22, candStart:-1, candEnd:-1
(b2) oldSelStart:22, oldSelEnd:22, newSelStart:1, newSelEnd:1, candStart:0, candEnd:1
(b3) oldSelStart:1, oldSelEnd:1, newSelStart:0, newSelEnd:0, candStart:-1, candEnd:-1

(b3) is called since Google Japanese Input clears composition by (b2).
If (b1) is not called, IME (at least Google Japanese Input) works fine.

Able to reproduce the issue. Observed the typed letter is shown, but going off immediately.

Steps Followed:
1. Installed Google Japanese Input Launched Browser
2. Launched Browser
3. Navigated to http://pc.watch.impress.co.jp/ 
4. Tapped OmniBox
5. Observed the typed letter is shown, but going off immediately.

Chrome versions tested:
61.0.3163.98, 63.0.3236.6

OS
Android 7.1.2

Android Devices
7.1.2 Pixel XL Build/N2G48E

This seems to be a Non-Regression issue as same behavior is seen since M50. Untriaged for further input's on this issue.

Removing Needs-Bisect label for now add it back if required.

Issue is seen in M63 as well.

Please navigate to below link for log's and video--
go/chrome-androidlogs/773197

Thanks!!

Thanks for looking into it, I can take a look when I have time. Lowering to P3 as this is not a regression.

Thank you for taking a look.

Note that this issue is not observed several months before (at least on my environment).
Since this issue is observed on M50, I think the contents of pc.wath.impress.co.jp are updated and it causes issue.

hsumnita@, yukawa@, what are the most popular Japanese IMEs? I'd like to test Japanese more extensively. So far I've been using the following for Japanese:

Google Japanese Keyboard
Samsung keyboard
ATOK trial
Shimeji
Japanese Keyboard by Umbrella
IQQI Japanese

Is iWnn popular? What other keyboards do I have to consider?

- iWnn is bundled on SHARP devices (10.4%) and Kyocera (7.6%).
- PO Box Plus is bundled on Sony devices (12.6%).

The above numbers show the market share in Japan @ 2016.
https://www.idcjapan.co.jp/Press/Current/20170221Apr.html
https://www.idcjapan.co.jp/Press/Current/20170221_4.gif
Note that Fujitsu bundles ATOK.

hsumita@, thanks a lot for the information! cc'ing other people for #8.