Rename flag IS_DOGFOOD to IS_STUDIO.

The flag is only set when building from Android Studio... and is never
used for dogfood.

Test: local
Change-Id: I898d585f4558c2437f0152ef102bea59c351f80b

src/com/android/launcher3/PagedView.java

@@ -1502,7 +1502,7 @@ public abstract class PagedView<T extends View & PageIndicator> extends ViewGrou
             return false;
         }
 
-        if (FeatureFlags.IS_DOGFOOD_BUILD) {
+        if (FeatureFlags.IS_STUDIO_BUILD) {
             duration *= Settings.Global.getFloat(getContext().getContentResolver(),
                     Settings.Global.WINDOW_ANIMATION_SCALE, 1);
         }