Upstream changes to resolveAssetSource.js

Summary

We need to override Libraries/Image/resolveAssetSource.js for unpackaged apps. There are assumptions in the upstream version of resolveAssetSource.js that the root bundle path is of the form <protocol>://<path>, and unpackaged apps may use bundle root paths of the form "C:<path>" or otherwise.

Motivation

We ship both packaged and unpackaged versions of our app. We should support both scenarios.

Currently, react-native-windows has a bug where the source code URL for bundled apps is an empty string. We'll be fixing this so that apps can reliably use the Image.resolveAssetSource API from React Native to get a fully qualified path to a packaged asset.

In order for this bug fix to work with unpackaged apps, we need eliminate the assumption that bundle paths match the form <protocol>://<path>.

Basic Example

For example, in our app, we have a context menu native module that takes in an object including the URI for the Icon to use for a context menu item. It should be possible to use the Image.resolveAssetPath API to resolve the fully qualified asset path for the icon.

E.g.,

const icon = require('icon.png');
const iconSource = Image.resolveAssetSource(icon);
NativeModules.ContextMenu.show({text: 'Item 1', icon: iconSource});

Without this change, unpackaged app icon sources will always be resolved to file://icon.png and we need native logic in the context menu module to strip the file:// prefix and prepend the bundle root path from the instance settings snapshot.

I'd prefer that we have common logic that is reusable for all modules that works in roughly the same way resolveAssetSource behaves on other platforms.

Open Questions

No response

Start with Libraries/Image/resolveAssetSource.js and inspect how it parses the bundle root path for packaged and unpackaged apps. Verify the behavior of Image.resolveAssetSource with paths such as C:<path> and protocol-based roots; done means both scenarios return a fully qualified asset path without requiring native modules to rewrite it.