Moving this nonessential bug to the next milestone.

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This issue has been moved once and is lower than Pri-1. Removing the milestone.

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

Repro'ed on M54/8735.0.0/link.

This seems a pdf pepper plugin bug.

This issue can repro even with any IMEs with composing text (e.g. Chinese Pinyin IME).

The floating candidate window is actually a view for composing text which is (I think) provided by the pdf pepper plugin.

On other platform, such as Windows, there is no view for composing text, which may be a separated issue.

+thestig@ +jam@ who may know more about pdf.

+kinaba@ in case this is related to IME support in the pepper api.

Do we know if this is a regression?

What's the repro steps on Link? It doesn't have a tablet mode.

Possible to repro on Linux, right? Just use whatever Chinese IME I can find on Ubuntu?

> Do we know if this is a regression?
Sorry, I am not sure.

> What's the repro steps on Link? It doesn't have a tablet mode.
You can enable the flag --enable-virtual-keyboard to bring up VK.
Or you can repro this issue by using Chinese Pinyin input method (enable via chrome://settings/languages)

> Possible to repro on Linux, right? Just use whatever Chinese IME I can find on Ubuntu?
No, it seems that the pdf plugin on Linux doesn't support inline composing view and has different behaviors.
Please repro this on you Link device. With Chinese Pinyin input method, you can type "ni" and see the suggestion window pops up, the composing view shows "ni" in the input field in the PDF plugin, and then click/tap the omnibox.

How about with the "ChromeOS on Linux" build + Chinese Pinyin input method? I have not flashed a Chromebook in a while and it would be nice if I can avoid it. Maybe I will try that when I get a chance.

Additionally, I'm not an IME expert, so if anyone has a better idea of what is going wrong, please feel free to grab this bug.

I did manage to get the Chinese Pinyin IME popup to get stuck in an open state on Link. Sadly I cannot get the same IME to work in "ChromeOS on Linux". Debugging this is going to be a lot more painful.

Please unzip the following package to /usr/share/chromeos-assets/input_methods/input_tools/.
(Make sure you got the file background.html under it).
https://drive.google.com/a/chromium.org/file/d/0B3DI9yQGnfcbXzZ2R0h1akNibFE/view?usp=sharing

Also, please make sure you built your "ChromeOS on Linux" with buildtype=Official and branding=Chrome.

Sorry, I wanna help but swamped with other task right now...

The floating view that's failing to be dismissed is the |preedit_| view here
https://cs.chromium.org/chromium/src/ui/chromeos/ime/candidate_window_view.cc?dr=CSs&sq=package:chromium&l=227

I guess something is missing to dismiss the view when the whole composition session is canceled.
E.g., SetCandidateWindowVisible() updating only the lookup table looks fishy. (Though I haven't tested anything)
https://cs.chromium.org/chromium/src/chrome/browser/chromeos/input_method/input_method_engine.cc?dr=CSs&sq=package:chromium&rcl=1472469725&l=119

Sorry, please ignore the misleading comment #6, the floating view is indeed the candidate window view.

Taking over the issue and working on the fix.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/2820bbca0e3e9fa68df28eb4831e8d0471926aac

commit 2820bbca0e3e9fa68df28eb4831e8d0471926aac
Author: shuchen <shuchen@chromium.org>
Date: Tue Aug 30 06:30:00 2016

The preedit view of the candidate window should be hidden correctly when the text input client doesn't support inline composing.

BUG= 612642 

Review-Url: https://codereview.chromium.org/2290083002
Cr-Commit-Position: refs/heads/master@{#415225}

[modify] https://crrev.com/2820bbca0e3e9fa68df28eb4831e8d0471926aac/chrome/browser/chromeos/input_method/candidate_window_controller_impl.cc
[modify] https://crrev.com/2820bbca0e3e9fa68df28eb4831e8d0471926aac/ui/base/ime/input_method_chromeos.cc

Reproduce the issue on Chrome 54.0.2840.45/CrOS 8743.46.0 - Glimmer

======

Able to reproduce the issue  with CJK IME on non-touch screen device. 54.0.2840.45/CrOS 8743.46.0 0 Winky

Steps :
Steps :
1.  open https://www.irs.gov/pub/irs-pdf/fw4.pdf 
2.  set IME to Korean 
3.  enter "gks",한 
4.  close the pdf file before committing the input

Then IME composing view isn't dismissed until resetting IME. 

This is not fixed in M54 but fixed in M55.

Btw, the floating IME composing view is mis-positioned at the left-bottom corner of the screen, although it can be hidden correctly.

And that should be a separated issue.