Use bitmap-based glyph metrics instead of outline-based metrics

Use bitmap-based glyph metrics instead of outline-based metrics
when applicable embedded bitmap exists in TTF
because if we use outline-metrics for embedded bitmap
it will be drawn incompletely.

BUG=1138
--

please refer to:
https://bugs.webkit.org/show_bug.cgi?id=105694
https://code.google.com/p/skia/issues/detail?id=1138

[bungeman-skia, 2013-03-06 14:48:42]

Thank you for suggesting this change, as it does help to point out a means of
solving this issue. However, there is a great deal of other code which will need
to be removed or changed to properly handle this. I am currently working on such
a change, but it may take some time as it will affect advance widths and
character placements, leading to the necessity of large re-baseline (in
chromium/webkit).

[takao, 2013-03-07 08:45:38]

Thank you, bungeman.
Please let me make sure of the following.

1. Does it mean that some other code will get buggy if my patch was simply
applied?
2. (Otherwise) could you use my patch as makeshift at first?

Sorry for the inconvenience.

[bungeman-skia, 2013-03-07 14:58:32]

On 2013/03/07 08:45:38, takao wrote:
> Thank you, bungeman.
> Please let me make sure of the following.
> 
> 1. Does it mean that some other code will get buggy if my patch was simply
> applied?
> 2. (Otherwise) could you use my patch as makeshift at first?
> 
> Sorry for the inconvenience.

Applying your patch changes text rendering in general for many fonts, not just
this one isolated case. Many glyph advances and glyph origins are different,
resulting in very large changes to text rendering in general. We are currently
investigating what the effects are and what to do about them.

[takao, 2013-03-07 17:17:30]

Oh, I got it.
It sounds tough, thank you for your endeavors.

[bungeman-skia, 2013-03-08 23:12:52]

On 2013/03/07 17:17:30, takao wrote:
> Oh, I got it.
> It sounds tough, thank you for your endeavors.

I have opened https://codereview.appspot.com/7635045/ for my proposed change
which builds on this one.

[takao, 2013-03-11 10:45:08]

I see.
I have no complaints with the new version.

[bungeman-skia, 2013-03-11 21:09:29]

https://codereview.appspot.com/7635045/ has landed with
https://code.google.com/p/skia/source/detail?r=8069 .