optimize-ico-files: Automatically rebuild the AND mask of 32-bit images.

optimize-ico-files: Automatically rebuild the AND mask of 32-bit images.

Due to a bug in Windows, icons do not display properly in some contexts
if the AND mask has transparency on a pixel that is partially (or fully)
opaque (see crbug.com/526622,
https://bugzilla.gnome.org/show_bug.cgi?id=755200). GIMP <=2.8.14 (and
possibly other icon tools) generates icons that do not satisfy this
property. This is a work-around for that issue.

The optimize-ico-files script (which is supposed to be run on all .ico
files in Chrome, according to chrome/app/theme/README) now strips out
the AND mask for any 32-bit image and rebuilds it from the alpha
channel. This ensures that it displays properly on Windows regardless of
which tool created it.

BUG=534679
Committed: https://crrev.com/196c33780897dbb87d9fb2c8cd0449096269103c
Cr-Commit-Position: refs/heads/master@{#351683}

[Matt Giuca, 2015-09-28 02:54:25]

mgiuca@chromium.org changed reviewers:
+ oshima@chromium.org

[oshima, 2015-09-30 19:26:44]

lgtm

https://codereview.chromium.org/1372843002/diff/20001/chrome/app/theme/README
File chrome/app/theme/README (right):

https://codereview.chromium.org/1372843002/diff/20001/chrome/app/theme/README...
chrome/app/theme/README:45: masks.
nit: a link to the bug?

[Matt Giuca, 2015-10-01 00:26:08]

https://chromiumcodereview.appspot.com/1372843002/diff/20001/chrome/app/theme...
File chrome/app/theme/README (right):

https://chromiumcodereview.appspot.com/1372843002/diff/20001/chrome/app/theme...
chrome/app/theme/README:45: masks.
On 2015/09/30 19:26:43, oshima wrote:
> nit: a link to the bug?

Done.

[Matt Giuca, 2015-10-01 00:26:21]

The CQ bit was checked by mgiuca@chromium.org

[Matt Giuca, 2015-10-01 00:26:21]

The patchset sent to the CQ was uploaded after l-g-t-m from oshima@chromium.org
Link to the patchset: https://chromiumcodereview.appspot.com/1372843002/#ps40001
(title: "Added link to bug.")

[commit-bot: I haz the power, 2015-10-01 00:26:36]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1372843002/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1372843002/40001

[commit-bot: I haz the power, 2015-10-01 00:40:38]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-10-01 00:41:27]

Patchset 3 (id:??) landed as
https://crrev.com/196c33780897dbb87d9fb2c8cd0449096269103c
Cr-Commit-Position: refs/heads/master@{#351683}