Several animation calls cleanup

> Using View property instead of strings to avoid extra reflection step
> Using ViewPropertyAnimator when several properties are being animated

Change-Id: I41625643b38b70bac11e2c81d18058ec878d73bd

src/com/android/launcher3/testing/LauncherExtension.java

@@ -330,7 +330,8 @@ public class LauncherExtension extends Launcher {
             @Override
             public void onScrollInteractionEnd() {
                 if (mProgress > 25 && mLauncherOverlayCallbacks.enterFullImmersion()) {
-                    ObjectAnimator oa = LauncherAnimUtils.ofFloat(mSearchOverlay, "translationX", 0);
+                    ObjectAnimator oa = LauncherAnimUtils.ofFloat(
+                            mSearchOverlay, View.TRANSLATION_X, 0);
                     oa.addListener(new AnimatorListenerAdapter() {
                         @Override
                         public void onAnimationEnd(Animator arg0) {