borealis: Add placeholder icons

For now these icons are only used by the installer. Going forward they
will be used as a fallback icon in the event that a borealis app doesn't
provide its own.

These PNGs were optimized with:
tools/resources/optimize-png-files.sh -o2 chrome/app/theme/borealis/

Bug: b/163431457
Change-Id: I4e95720093c137d3a5e64ddca8c9a17a905844ae
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2377770
Commit-Queue: Nic Hollingum <hollingum@google.com>
Reviewed-by: Nancy Wang <nancylingwang@chromium.org>
Reviewed-by: Mitsuru Oshima (Slow: gardener) <oshima@chromium.org>
Cr-Commit-Position: refs/heads/master@{#805632}

chrome/app/theme/chrome_unscaled_resources.grd

@@ -118,6 +118,8 @@
         <include name="IDR_APPS_FOLDER_OVERLAY_512" file="mac/apps_folder_overlay_512.png" type="BINDATA" />
       </if>
       <if expr="chromeos">
+        <!-- Borealis icons -->
+        <include name="IDR_LOGO_BOREALIS_DEFAULT_192" file="borealis/logo_borealis_default_192.png" type="BINDATA" />
         <!-- Crostini icons -->
         <include name="IDR_LOGO_CROSTINI_TERMINAL" file="crostini/logo_crostini_terminal.png" type="BINDATA" />
         <include name="IDR_LOGO_CROSTINI_DEFAULT_32" file="crostini/logo_crostini_default_32.png" type="BINDATA" />

chrome/browser/apps/app_service/borealis_apps.cc

@@ -39,10 +39,9 @@ apps::mojom::AppPtr GetBorealisLauncher(Profile* profile, bool allowed) {
       l10n_util::GetStringUTF8(IDS_BOREALIS_APP_NAME),
       apps::mojom::InstallSource::kUser);
 
-  // TODO (b/163431457): use borealis icon.
   app->icon_key = apps::mojom::IconKey::New(
       apps::mojom::IconKey::kDoesNotChangeOverTime,
-      IDR_LOGO_CROSTINI_DEFAULT_192, apps::IconEffects::kNone);
+      IDR_LOGO_BOREALIS_DEFAULT_192, apps::IconEffects::kNone);
 
   SetAppAllowed(app.get(), allowed);
   return app;