Updating paging animation to spec.

- To handle the specific animation spec, we just animate the views
  manually instead of animating the stack scroll (like how we do when
  swiping to dismiss)
- Fixing a regression in settings the initial focused index when
  alt-tabbing
- Minor tweak to make the front most task smaller when in the initial
  non-paging mode

Change-Id: Ic5fd54500fd8ce8284c7aaeddb102b2291bcecac

Signed-off-by: Winson <winsonc@google.com>
diff --git a/packages/SystemUI/src/com/android/systemui/recents/RecentsActivityLaunchState.java b/packages/SystemUI/src/com/android/systemui/recents/RecentsActivityLaunchState.java
index f7ebd94..82e7861 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/RecentsActivityLaunchState.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/RecentsActivityLaunchState.java
@@ -66,8 +66,9 @@
      */
     public int getInitialFocusTaskIndex(int numTasks) {
         RecentsDebugFlags debugFlags = Recents.getDebugFlags();
+        RecentsActivityLaunchState launchState = Recents.getConfiguration().getLaunchState();
         if (launchedFromAppWithThumbnail) {
-            if (debugFlags.isFastToggleRecentsEnabled()) {
+            if (!launchState.launchedWithAltTab && debugFlags.isFastToggleRecentsEnabled()) {
                 // If fast toggling, focus the front most task so that the next tap will focus the
                 // N-1 task
                 return numTasks - 1;
@@ -76,7 +77,7 @@
             // If coming from another app, focus the next task
             return numTasks - 2;
         } else {
-            if (debugFlags.isFastToggleRecentsEnabled()) {
+            if (!launchState.launchedWithAltTab && debugFlags.isFastToggleRecentsEnabled()) {
                 // If fast toggling, defer focusing until the next tap (which will automatically
                 // focus the front most task)
                 return -1;