Empty inline elements always get a line box.

Empty inline elements always get a line box.

CSS 2.1 (http://www.w3.org/TR/CSS2/visudet.html#leading) says: "Empty inline 
elements generate empty inline boxes, but these boxes still have margins, padding, 
borders and a line height, and thus influence [line-height calculation] just 
like elements with content."

We weren't creating lineboxes for empty inline elements when they occurred
between a single trailing space and a single leading space - this is because
our linebox creation was based on the too-narrow premise that we were already
ignoring spaces. However, if an empty inline element comes after a trailing 
space but before one or more leading spaces then it will be ignored as part 
of the collapsed space between the trailing space and the next non-collapsible 
space - so we should force the creation of a linebox in such cases.

This allows us to pass Hixie's empty inline test: 
http://www.hixie.ch/tests/evil/mixed/emptyinline.html

BUG=328939
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=177605

[rhogan, 2014-05-27 21:40:03]

https://codereview.chromium.org/300853007/diff/1/Source/platform/text/BidiRes...
File Source/platform/text/BidiResolver.h (left):

https://codereview.chromium.org/300853007/diff/1/Source/platform/text/BidiRes...
Source/platform/text/BidiResolver.h:76: Iterator midpoint(0,
textParagraphSeparator.object(), textParagraphSeparator.offset());
This is a redundant line of code I noticed when adding the function above.

[leviw_travelin_and_unemployed, 2014-05-30 00:15:17]

Dang, good fix! LGTM!

[rhogan, 2014-05-31 20:29:38]

The CQ bit was checked by robhogan@gmail.com

[commit-bot: I haz the power, 2014-05-31 20:30:00]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/robhogan@gmail.com/300853007/20001

[commit-bot: I haz the power, 2014-05-31 20:43:54]

Change committed as 175205

[rhogan, 2014-05-31 22:01:29]

A revert of this CL has been created in
https://codereview.chromium.org/302233002/ by robhogan@gmail.com.

The reason for reverting is: This changed the subpixel positioning of glyphs on
lines with first-letter renderers on Mac builds. See
https://storage.googleapis.com/chromium-layout-test-archives/WebKit_Mac10_6/2...
as an example.

I think the new results are benign - but would like to confirm with leviw and
reland as NeedsRebaseline if we're both happy with them.
.

[rhogan, 2014-06-01 08:15:24]

The CQ bit was checked by robhogan@gmail.com

[commit-bot: I haz the power, 2014-06-01 08:15:30]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/robhogan@gmail.com/300853007/20001

[commit-bot: I haz the power, 2014-06-01 08:15:57]

Change committed as 175218

[rhogan, 2014-06-01 08:20:57]

On 2014/05/31 22:01:29, rhogan wrote:
> A revert of this CL has been created in
> https://codereview.chromium.org/302233002/ by mailto:robhogan@gmail.com.
> 
> The reason for reverting is: This changed the subpixel positioning of glyphs
on
> lines with first-letter renderers on Mac builds. See
>
https://storage.googleapis.com/chromium-layout-test-archives/WebKit_Mac10_6/2...
> as an example.
> 
> I think the new results are benign - but would like to confirm with leviw and
> reland as NeedsRebaseline if we're both happy with them.
> .

Turns out this wasn't me at all: https://codereview.chromium.org/306083006

So relanding.

[rhogan, 2014-07-07 19:52:58]

On 2014/06/01 at 08:20:57, rhogan wrote:
> On 2014/05/31 22:01:29, rhogan wrote:
> > A revert of this CL has been created in
> > https://codereview.chromium.org/302233002/ by mailto:robhogan@gmail.com.
> > 
> > The reason for reverting is: This changed the subpixel positioning of glyphs
on
> > lines with first-letter renderers on Mac builds. See
> >
https://storage.googleapis.com/chromium-layout-test-archives/WebKit_Mac10_6/2...
> > as an example.
> > 
> > I think the new results are benign - but would like to confirm with leviw
and
> > reland as NeedsRebaseline if we're both happy with them.
> > .
> 
> Turns out this wasn't me at all: https://codereview.chromium.org/306083006
> 
> So relanding.

This was reverted again in:

https://code.google.com/p/chromium/issues/detail?id=387211

See also https://code.google.com/p/chromium/issues/detail?id=381526

However per my comment there
(https://code.google.com/p/chromium/issues/detail?id=387211#c29) the actual
culprit was: http://src.chromium.org/viewvc/blink?view=rev&revision=175220

So I'm relanding this change again. I ok'd this with inferno-sec:
https://code.google.com/p/chromium/issues/detail?id=381526#c21

[rhogan, 2014-07-07 19:53:36]

The CQ bit was checked by robhogan@gmail.com

[commit-bot: I haz the power, 2014-07-07 19:54:23]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/robhogan@gmail.com/300853007/20001

[commit-bot: I haz the power, 2014-07-07 20:56:37]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  android_chromium_gn_compile_rel on tryserver.blink
(http://build.chromium.org/p/tryserver.blink/builders/android_chromium_gn_comp...)

[commit-bot: I haz the power, 2014-07-07 21:29:15]

Change committed as 177605