Refactor logo usage (opensearch-project#4702)

Also:
* Move logos to a central location
* Make the loading spinner color-scheme-aware
* Recreate `OverviewPageHeader`, `HomeIcon`, `HeaderLogo`, `SolutionTitle`, `Welcome`, `Overview` tests
* Enhance `ExitFullScreenButton`, `Header` tests
* Tinified favicon assets

Signed-off-by: Miki <miki@amazon.com>

(cherry picked from commit d7c5577)
Signed-off-by: Miki <miki@amazon.com>

CHANGELOG.md

@@ -44,6 +44,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - Replace the use of `bluebird` in `saved_objects` plugin ([#4026](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4026))
 - [Table Visualization] Remove custom styling for text-align:center in favor of OUI utility class. ([#4164](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4164))
 - [Dashboard] Restructure the `Dashboard` plugin folder to be more cohesive with the project ([#4575](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4575))
+- Refactor logo usage to centralize and optimize assets and improve tests ([#4702](https://github.com/opensearch-project/OpenSearch-Dashboards/pull/4702))
 
 ### 🔩 Tests
 

packages/osd-dev-utils/src/serializers/flat_object_serializer.ts

@@ -0,0 +1,93 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+const walk = (value: any, path: string[] = [], collector: string[] = []) => {
+  let objValue;
+  switch (Object.prototype.toString.call(value)) {
+    case '[object Map]':
+    case '[object WeakMap]':
+      // Turn into an Object so it can be iterated
+      objValue = Object.fromEntries(value);
+      break;
+
+    case '[object Set]':
+    case '[object WeakSet]':
+      // Turn into an Array so it can be iterated
+      objValue = Array.from(value);
+      break;
+
+    case '[object Object]':
+    case '[object Array]':
+      objValue = value;
+      break;
+
+    case '[object RegExp]':
+    case '[object Function]':
+    case '[object Date]':
+    case '[object Boolean]':
+    case '[object Number]':
+    case '[object Symbol]':
+    case '[object Error]':
+      collector.push(`${path.join('.')} = ${value.toString()}`);
+      break;
+
+    case '[object Null]':
+      collector.push(`${path.join('.')} = null`);
+      break;
+
+    case '[object Undefined]':
+      collector.push(`${path.join('.')} = undefined`);
+      break;
+
+    case '[object String]':
+      collector.push(`${path.join('.')} = ${JSON.stringify(value)}`);
+      break;
+
+    case '[object BigInt]':
+      collector.push(`${path.join('.')} = ${value.toString()}n`);
+      break;
+
+    default:
+      // if it is a TypedArray, turn it into an array
+      if (value instanceof Object.getPrototypeOf(Uint8Array)) {
+        objValue = Array.from(value);
+      }
+  }
+
+  // If objValue is set, it is an Array or Object that can be iterated; else bail.
+  if (!objValue) return collector;
+
+  if (Array.isArray(objValue)) {
+    objValue.forEach((v, i) => {
+      walk(v, [...path, i.toString()], collector);
+    });
+  } else {
+    // eslint-disable-next-line guard-for-in
+    for (const key in objValue) {
+      walk(objValue[key], [...path, key], collector);
+    }
+  }
+
+  return collector;
+};
+
+/**
+ * The serializer flattens objects into dotified key-value pairs, each on a line, and
+ * sorts them to aid in diff-ing.
+ *
+ * Example:
+ * { K: ["a", "b", { X: 1n }], Y: 1}
+ *
+ * Serialized:
+ * K.0 = "a"
+ * K.1 = "b"
+ * K.2.X = 1n
+ * Y = 1
+ */
+export const flatObjectSerializer = {
+  test: (value: any) =>
+    ['[object Object]', '[object Array]'].includes(Object.prototype.toString.call(value)),
+  serialize: (value: any) => walk(value).sort().join('\n'),
+};

packages/osd-dev-utils/src/serializers/index.ts

@@ -34,3 +34,4 @@ export * from './recursive_serializer';
 export * from './any_instance_serizlizer';
 export * from './replace_serializer';
 export * from './strip_promises_serizlizer';
+export * from './flat_object_serializer';

src/core/common/index.ts

@@ -0,0 +1,7 @@
+/*
+ * Copyright OpenSearch Contributors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+export { ImageType, ColorScheme, getLogos } from './logos';
+export type { Logos } from './types';