Fix icons in gallery, demo and cast (#19732)

* Fix icons in gallery and demo

* Add to lovelace gallery

* Update icons.ts

* add BACKWARDS_COMPAT support for icons

* Update entity-state.ts

* Update icons.ts

* Update icons.ts

demo/src/ha-demo.ts

@@ -17,6 +17,7 @@ import { energyEntities } from "./stubs/entities";
 import { mockEntityRegistry } from "./stubs/entity_registry";
 import { mockEvents } from "./stubs/events";
 import { mockFrontend } from "./stubs/frontend";
+import { mockIcons } from "./stubs/icons";
 import { mockHistory } from "./stubs/history";
 import { mockLovelace } from "./stubs/lovelace";
 import { mockMediaPlayer } from "./stubs/media_player";
@@ -57,6 +58,7 @@ export class HaDemo extends HomeAssistantAppEl {
     mockEvents(hass);
     mockMediaPlayer(hass);
     mockFrontend(hass);
+    mockIcons(hass);
     mockEnergy(hass);
     mockPersistentNotification(hass);
     mockConfigEntries(hass);

demo/src/stubs/icons.ts

@@ -0,0 +1,33 @@
+import { IconCategory } from "../../../src/data/icons";
+import { ENTITY_COMPONENT_ICONS } from "../../../src/fake_data/entity_component_icons";
+import { MockHomeAssistant } from "../../../src/fake_data/provide_hass";
+
+export const mockIcons = (hass: MockHomeAssistant) => {
+  hass.mockWS(
+    "frontend/get_icons",
+    async ({
+      category,
+      integration,
+    }: {
+      category: IconCategory;
+      integration?: string;
+    }) => {
+      if (integration) {
+        try {
+          const response = await fetch(
+            `https://raw.githubusercontent.com/home-assistant/core/dev/homeassistant/components/${integration}/icons.json`
+          ).then((resp) => resp.json());
+          return { resources: { [integration]: response[category] || {} } };
+        } catch {
+          return { resources: {} };
+        }
+      }
+      if (category === "entity_component") {
+        return {
+          resources: ENTITY_COMPONENT_ICONS,
+        };
+      }
+      return { resources: {} };
+    }
+  );
+};