Pass http:// prefix in VR source map URLs

Summary:
Horizon devs use the Chrome debugging protocol which has the similar `http://` protocol expectation as explained in the comment here.

After fb-metro upgrade, the `//` protocol is being used which breaks source mapping when debugging Horizon. Fix it by including `vr` in the platform check here.

Is there any chance this would break debugging for some other users who might still be passing VR as platform? I feel like it's safe but just checking. Not sure a good way to fix this otherwise

Reviewed By: motiz88

Differential Revision: D49936311

fbshipit-source-id: b4b1d1c16412393691a7d943c7af3467836a78b2

packages/metro/src/lib/parseOptionsFromUrl.js

@@ -74,8 +74,9 @@ module.exports = function parseOptionsFromUrl(
       // protocol is blob:http. This breaks loading source maps through
       // protocol-relative URLs, which is why we must force the HTTP protocol
       // when loading the bundle for either Android or iOS.
+      // TODO(T167298674): Remove when remote debugging is not needed in React Native
       protocol:
-        platform != null && platform.match(/^(android|ios)$/) ? 'http' : '',
+        platform != null && platform.match(/^(android|ios|vr)$/) ? 'http' : '',
       pathname: pathname.replace(/\.(bundle|delta)$/, '.map'),
     }),
     sourceUrl: jscSafeUrl.toJscSafeUrl(normalizedRequestUrl),