1296217 - [e10s] Suggest window and candidate window of IME isn't positioned as expected if the editor is zoomed in/out or rotated by CSS transform

Status: RESOLVED FIXED

Description

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)(Still struggling with the pain, but becoming better)]

I realized that suggest window and candidate window of IME isn't positioned correctly only in e10s mode if focused editor is zoomed in/out or rotated by CSS transform.

I'm not sure why it works well with translate...

# Although, this is a bug in edge case, so, I cannot work on this soon.  If you try to fix this bug, feel free to take this!

Comment 1

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)(Still struggling with the pain, but becoming better)]

https://treeherder.mozilla.org/#/jobs?repo=try&revision=644efab95f2a

Comment 2

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)(Still struggling with the pain, but becoming better)]

Attachment: Bug 1296217 ContentEventHandler::OnQueryTextRectArray() should apply CSS transform to each character or line breaker rect

Currently, ContentEventHandler::OnQueryTextRectArray() is used only in e10s mode (at caching necessary character rects in ContentCacheInChild).  Therefore, this bug occurs only in e10s mode.

ContentEventHandler::OnQueryTextRectArray() applies CSS transform only to each frame rect.  Therefore, character rect's width and height are not applied.

This patch makes the loop apply CSS transform to each character or line breaker rect (i.e., each item of charRects).  Then, we need to rewrite the lastCharRect hack.  It stores the last charRect value for computing next line breaker rect if next line breaker is caused by a block level element or something, i.e., not caused by a <br> frame.  So, when brRect is computed with lastCharRect, the loop needs to apply CSS transform of the last text frame to the following brRect because it tries to compute a caret rect immediately after the last character.  For doing this, this patch adds lastFrame which stores the last frame for lastCharRect and set it to baseFrame.  Then, at applying CSS transform to each charRect, it can apply CSS transform of expected frame.

Similarly, when brRect is computed with last text frame, this patch looks for the last text frame from lastTextContent and use it as base frame to apply to CSS transform.

Review commit: https://reviewboard.mozilla.org/r/76968/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/76968/

Comment 3

[Olli Pettay [:smaug]]

Comment on attachment 8788470 [details]
Bug 1296217 ContentEventHandler::OnQueryTextRectArray() should apply CSS transform to each character or line breaker rect

https://reviewboard.mozilla.org/r/76968/#review75226

I assume you tested this all also when focus was in some iframe.

Comment 4

[Masayuki Nakano [:masayuki] (he/him)(JST, +0900)(Still struggling with the pain, but becoming better)]

(In reply to Olli Pettay [:smaug] from comment #3)
> I assume you tested this all also when focus was in some iframe.

Yeah, the URL, jsfiddle.net, runs the testcase in iframe and I tested in it. Additionally, bug 1291172 checks this bug too.

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/8a0e581059cc
ContentEventHandler::OnQueryTextRectArray() should apply CSS transform to each character or line breaker rect r=smaug

Comment 6

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/8a0e581059cc