[Extensions UI] Add a placeholder icon for extensions in the toolbar

[Extensions UI] Add a placeholder icon for extensions in the toolbar

Create a placeholder icon source for extensions that don't have an icon, so that
they don't just look like puzzle pieces in the toolbar.
To start, only use this in the toolbar, but the class is flexible enough that
it could also be used, e.g., in the chrome://extensions page.

BUG=486206
Committed: https://crrev.com/a437dab3e6f188c53f452b35198b770b33a8aa96
Cr-Commit-Position: refs/heads/master@{#329932}

[Devlin, 2015-05-08 23:15:47]

rdevlin.cronin@chromium.org changed reviewers:
+ finnur@chromium.org

[Devlin, 2015-05-08 23:15:47]

Take your time - I'm out until Thursday of next week, so no rush. :)

[Finnur, 2015-05-13 15:46:37]

LGTM, if there's no localization concern (see below).

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
File extensions/browser/extension_icon_placeholder.cc (right):

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
extensions/browser/extension_icon_placeholder.cc:49: // that will be done
frequently, we should probably make a devoted assest for
nit: s/assest/asset/

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
extensions/browser/extension_icon_placeholder.cc:57: resource_id =
IDR_EXTENSION_ANONYMOUS_ACTION_BACKGROUND;
nit: This naming bugs me a bit. It's not for a background action that is
anonymous. It's also not for an extension that is anonymous (especially since
you are using the first letter of the name to draw upon it). What about just:

IDR_EXTENSION_ICON_PLAIN_BACKGROUND
IDR_EXTENSION_ACTION_PLAIN_BACKGROUND

... and png file names to match?

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
extensions/browser/extension_icon_placeholder.cc:76:
letter_(StringToUpperASCII(base::UTF8ToUTF16(letter.substr(0, 1)))),
Does this work well (considering localization)?

[Devlin, 2015-05-14 20:23:48]

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
File extensions/browser/extension_icon_placeholder.cc (right):

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
extensions/browser/extension_icon_placeholder.cc:49: // that will be done
frequently, we should probably make a devoted assest for
On 2015/05/13 15:46:37, Finnur (OOO Thu -- holiday) wrote:
> nit: s/assest/asset/

Done.

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
extensions/browser/extension_icon_placeholder.cc:57: resource_id =
IDR_EXTENSION_ANONYMOUS_ACTION_BACKGROUND;
On 2015/05/13 15:46:37, Finnur (OOO Thu -- holiday) wrote:
> nit: This naming bugs me a bit. It's not for a background action that is
> anonymous. It's also not for an extension that is anonymous (especially since
> you are using the first letter of the name to draw upon it). What about just:
> 
> IDR_EXTENSION_ICON_PLAIN_BACKGROUND
> IDR_EXTENSION_ACTION_PLAIN_BACKGROUND
> 
> ... and png file names to match?

Yeah, that sounds better. :)  Done.

https://codereview.chromium.org/1131443006/diff/1/extensions/browser/extensio...
extensions/browser/extension_icon_placeholder.cc:76:
letter_(StringToUpperASCII(base::UTF8ToUTF16(letter.substr(0, 1)))),
On 2015/05/13 15:46:37, Finnur (OOO Thu -- holiday) wrote:
> Does this work well (considering localization)?

Good catch.  Probably not.  Moving to ASCII at all is lossy, so removing the
StringToUpperASCII call - which is probably fine anyway, since if an extension
really wants a lower-cased name, that's probably okay.  Taking the first
character and UTF8 -> UTF16 should be okay, though, I think.

[Devlin, 2015-05-14 20:23:56]

The CQ bit was checked by rdevlin.cronin@chromium.org

[Devlin, 2015-05-14 20:23:56]

The patchset sent to the CQ was uploaded after l-g-t-m from finnur@chromium.org
Link to the patchset: https://codereview.chromium.org/1131443006/#ps20001
(title: "Finnur's")

[commit-bot: I haz the power, 2015-05-14 20:26:47]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1131443006/20001

[commit-bot: I haz the power, 2015-05-14 21:16:44]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-05-14 21:17:45]

Patchset 2 (id:??) landed as
https://crrev.com/a437dab3e6f188c53f452b35198b770b33a8aa96
Cr-Commit-Position: refs/heads/master@{#329932}