Add setScreenOrientation to BaseUiAutomation class

This allows workloads to be launched in a pre-determined orientation not the orientation of the physical device itself.

Updated the productivity workloads to take advantage of this new facility.

wlauto/workloads/googlephotos/uiauto/src/com/arm/wlauto/uiauto/UiAutomation.java

@@ -43,12 +43,14 @@ public class UiAutomation extends UxPerfUiAutomation {
     public void runUiAutomation() throws Exception {
         parameters = getParams();
 
+        setScreenOrientation(ScreenOrientation.NATURAL);
         confirmAccess();
         dismissWelcomeView();
         gesturesTest();
         editPhotoColorTest();
         cropPhotoTest();
         rotatePhotoTest();
+        unsetScreenOrientation();
 
         writeResultsToFile(timingResults, parameters.getString("output_file"));
     }