====================================

Good Build:

50.0.2628.0    Base Position: 370939


Bad Build:

50.0.2629.0    Base Position: 371142

=====================================

Able to repro this issue on Windows 7, MAC (10.11.3) & Ubuntu Trusty (14.04) for the Google Chrome Canary Version - 51.0.2672.0

This is a regression issue broken in M50, below mentioned is the bisect info:

CHANGELOG URL: https://chromium.googlesource.com/chromium/src/+log/e0b6a82cadecbda7e005921c2416fc7afb3542aa..1fee3b4957164505e70df4152fa31a2807fefa74

Suspecting the below:

=============================================================

526a7f4c610f0f4a0859c199e8cd4fcedcb8234d 

Review URL: https://codereview.chromium.org/1618283006

======================= OR ==================================

e0906ef875c59ab9355e44e506b1e08f223844f2

Review URL: https://codereview.chromium.org/1613513004

=============================================================

@junov/dfalcantara: Could you please look into the issue, and if it has nothing to do with your changes and if possible please do assign it to the concerned owner.

Thank you.

Don't know who a concerned owner would be; mine is an Android-only change.  No possible way it could have affected blink, of all things.  Punting to junov.

rnimmagadda@, could you provide test page? 
It seems lots of steps need to get trial site.

Hi together,

i just checked the changelog. And just saw the change "Treat percent-height div inside auto-height cells as auto" (https://chromium.googlesource.com/chromium/src/+/8876584335b48c99cf8df552ef4d8efebb131041). As i have played around a bit with the CSS. The HTML Structure of that edit part is as following:
<div id="wysiwyg" style="width: 100%; height: 100%;">
   <div id="rte" class="cell editor-fullheight">
       <textarea id="wysiwygTextarea" name="wysiwygContent" class="hidden tinymce-editor" aria-hidden="true" style="display: none;"></textarea>
       <iframe id="wysiwygTextarea_ifr" src='javascript:""' frameborder="0" allowtransparency="true" title="{#aria.rich_text_area}" style="width: 100%; height: 100%; display: block;" tabindex="100"></iframe>
   </div>
</div>

The editor-fullheight class def looks like that:

.editor-fullheight {
    height: 100%;
}

So it is a 100% div in a 100% div. If i change the editor-fullheight height attribute to a pixel value (e.g. 500px) it grows to that value. So from my stumage feeling i would say this change interfers with old behavior.
I wasn't able to isolate it to that with an test page, that does only have that HTML snipped in it as the 49er Chrome version makes that editor div also that small like the 50 version. So there is maybe something that i am missing here around that block (but i can't provide full page source due to legal issues :( ).

But maybe this statement helps to find the root cause :)

As far as i can see this issue here is the same as mentioned in this comment: https://bugs.chromium.org/p/chromium/issues/detail?id=346275#c37

You may want to align with developers there especially about the guess with auto-height fix. :)

@yosin: Ran the bisect again and got the same result as mentioned in the comment #1

Test Page:

https://chrometesting69.atlassian.net/wiki/pages/editpage.action?pageId=1179655 [Please sign-up and create your login]

Please email me your email ID [separately], so that I can share the credentials.

Screen-recording is attached.

Thank you.

Deleted: 592931.mov 3.9 MB

592931.mov 3.9 MB Download

Changes to Blink>Layout, this is caused by changes of height:auto calculation between M49 and M51.

>#6,  rnimmagadda@, how do I sign up? I could not find "Sign Up" link in the URI specified in #6.

In below HTML, I saw "End of div" and "End of body" at bottom page and they are overlapped.

Per CSS spec, percentage "height" property is treated as "auto" if there is no containing box having explicit "height".

<style>
.editor-fullheight {
    height: 100%;
}
</style>
<div id="wysiwyg" style="width: 100%; height: 100%;">
   <div id="rte" class="cell editor-fullheight">
       <textarea id="wysiwygTextarea" name="wysiwygContent" class="hidden tinymce-editor" aria-hidden="true" style="display: none;"></textarea>
       <iframe id="wysiwygTextarea_ifr" src='javascript:""' frameborder="0" allowtransparency="true" title="{#aria.rich_text_area}" style="width: 100%; height: 100%; display: block;" tabindex="100"></iframe>End of div
   </div>
</div>
End of body

@yosin: Here is the link to Login - https://chrometesting69.atlassian.net/login?

 Issue 594987  has been merged into this issue.

This was an intentional change to match the spec and other browsers. Comment 7 above details the steps required to fix this issue.