Cross-platform version number retrieval (#2355)

* Add shim to retrieve application version.

* Create shim to retrieve app version number.

* Add a fall through handler to throw an error.

ReactNativeClient/lib/shim-init-node.js

@@ -378,6 +378,15 @@ function shimInit() {
 	};
 
 	shim.waitForFrame = () => {};
+
+	shim.appVersion = () => {
+		if (shim.isElectron()) {
+			const p = require('../packageInfo.js');
+			return p.version;
+		}
+		const p = require('../package.json');
+		return p.version;
+	};
 }
 
 module.exports = { shimInit };

ReactNativeClient/lib/shim-init-react.js

@@ -144,6 +144,11 @@ function shimInit() {
 		return Platform.OS;
 	};
 
+	shim.appVersion = () => {
+		const p = require('react-native-version-info').default;
+		return p.appVersion;
+	};
+
 	// NOTE: This is a limited version of createResourceFromPath - unlike the Node version, it
 	// only really works with images. It does not resize the image either.
 	shim.createResourceFromPath = async function(filePath, defaultProps = null) {

ReactNativeClient/lib/shim.js

@@ -197,6 +197,10 @@ shim.waitForFrame = () => {
 	throw new Error('Not implemented');
 };
 
+shim.appVersion = () => {
+	throw new Error('Not implemented');
+};
+
 shim.injectedJs = name => '';
 
 let isTestingEnv_ = false;