Improve image sizing for status icons

* Use 128x128 logo for the "background mode" status icon on Linux.
  * The 22x22 logo is now unused, so remove it.  [1] removes internal
    icons.
* Always use the highest resolution image representation that we're
  given, since all status icon implementations want to draw in pixel
  coordinates and we don't know in general how large the containing
  window will be.
* Change StatusIconLinuxX11 drawing logic to handle icon resizing.

[1] https://chrome-internal-review.googlesource.com/c/chrome/theme/google_chrome/+/1410578/

BUG=419673
R=thestig

Change-Id: I2cad9414ba24022b9305d808c8b30228ae5d5c17
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1671427
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Thomas Anderson <thomasanderson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#671514}
7 files changed