[doc] described mediaCapabilitiesInfo value

Author: anton-karlovskiy

README.md

@@ -200,6 +200,8 @@ const MyComponent = ({ videoSources }) => {
 };
 ```
 
+`mediaCapabilitiesInfo` value contains the three Boolean properties `supported`, `smooth`, and `powerefficient`, which describe whether decoding the media described would be supported, smooth, and powerefficient.
+
 This utility accepts a [MediaDecodingConfiguration](https://developer.mozilla.org/en-US/docs/Web/API/MediaDecodingConfiguration) object argument and an optional `initialMediaCapabilitiesInfo` object argument, which can be used to provide a `mediaCapabilitiesInfo` state value when the user's browser does not support the relevant [Media Capabilities API](https://developer.mozilla.org/en-US/docs/Web/API/Media_Capabilities_API) or no media configuration was given.
 
 ### Adaptive Code-loading & Code-splitting

media-capabilities/media-capabilities.test.js

@@ -86,7 +86,7 @@ describe('useMediaCapabilitiesDecodingInfo', () => {
     expect(result.current.mediaCapabilitiesInfo).toEqual({hasMediaDecodingConfig: false, supported: true});
   });
 
-  test('should return MediaCapabilitiesInfo for given media decoding configuration', () => {
+  test('should return MediaCapabilitiesInfo for given media configuration', () => {
     Object.defineProperty(window.navigator, 'mediaCapabilities', {
       value: {
         decodingInfo: mediaDecodingConfig => mediaCapabilitiesMapper[mediaDecodingConfig.audio.contentType]