Fix getSysInfo when paths to android tools are undefined

When paths to android tools are undefined, we call childProcess exec and spawnFromEvent with undefined commands.
This leads to futures left behind as childProcess cannot be created and our future is never resolved.
Do not call exec and spawnFromEvent in case command is empty.

Author: rosen-vladimirov

sys-info-base.ts

@@ -93,19 +93,25 @@ export class SysInfoBase implements ISysInfo {
 
 	private exec(cmd: string, execOptions?: IExecOptions): string | any {
 		try {
-			return this.$childProcess.exec(cmd, null, execOptions).wait();
+			if(cmd) {
+				return this.$childProcess.exec(cmd, null, execOptions).wait();
+			}
 		} catch(e) {
-			return null;
-		} // if we got an error, assume not working
+			// if we got an error, assume not working
+		}
+
+		return null;
 	}
 
 	// `android -h` returns exit code 1 on successful invocation (Mac OS X for now, possibly Linux). Therefore, we cannot use $childProcess
 	private checkAndroid(pathToAndroid: string): IFuture<boolean> {
 		return ((): boolean => {
 			let result = false;
 			try {
-				let androidChildProcess = this.$childProcess.spawnFromEvent(pathToAndroid, ["-h"], "close", {}, {throwError: false}).wait();
-				result = androidChildProcess && androidChildProcess.stdout && _.contains(androidChildProcess.stdout, "android");
+				if(pathToAndroid) {
+					let androidChildProcess = this.$childProcess.spawnFromEvent(pathToAndroid, ["-h"], "close", {}, {throwError: false}).wait();
+					result = androidChildProcess && androidChildProcess.stdout && _.contains(androidChildProcess.stdout, "android");
+				}
 			} catch(err) {
 				this.$logger.trace(`Error while checking is ${pathToAndroid} installed. Error is: ${err.messge}`);
 			}