Implementing mobile:background command for Android and Selendroid

lib/devices/android/android-common.js

@@ -14,6 +14,27 @@ var logTypesSupported = {
 
 var androidCommon = {};
 
+androidCommon.background = function(secs, cb) {
+    console.log("background " + this.appPackage + " " + this.appActivity);
+    this.adb.keyevent("3", function() {
+        cb(null, {
+            status: status.codes.Success.code
+            , value: null
+        });
+    });
+    setTimeout(function(){
+        var appName =   this.appActivity.replace(this.appPackage,this.appPackage + "/");
+        this.adb.shell("am start -n "+ appName, function(err, stdout) {
+            if (err) return cb(err);
+            if (stdout.indexOf("No such file") !== -1) {
+                return cb(new Error("remote apk did not exist"));
+            }
+            cb(null, stdout.trim());
+        });
+    }.bind(this),secs *1000) ;
+
+};
+
 androidCommon.prepareDevice = function(onReady) {
   logger.info("Preparing device for session");
   async.series([

lib/devices/android/android-controller.js

@@ -352,10 +352,6 @@ androidController.lock = function(secs, cb) {
     cb(new NotYetImplementedError(), null);
 };
 
-androidController.background = function(secs, cb) {
-    cb(new NotYetImplementedError(), null);
-};
-
 androidController.getOrientation = function(cb) {
   this.proxy(["orientation", {}], cb);
 };

lib/devices/android/selendroid.js

@@ -38,6 +38,7 @@ var Selendroid = function(opts) {
     , 'getCommandTimeout'
     , 'reset'
     , 'lock'
+    , 'background'
     , 'keyevent'
     , 'currentActivity'
     , 'installApp'