UI fixes to All apps pull up work

b/28917826
- nav bar change to light when top of the all apps container
passes y mid point of the status bar
- apps search edit box change when top of the all apps passes
the bottom of nav bar
- Restrict pull up to work only if the ACTION_DOWN event started
from the hotseat.
- Landscape: reverted old padding and margin. Only the interaction
is different.
- Tuning of the motion spec
- Animation duration respects fling speed more agressively.
- and many more small bugs...

Change-Id: Icde4093c41eeab8c9c6d9dc8b7d57adc3b171349

src/com/android/launcher3/WorkspaceStateTransitionAnimation.java

@@ -490,7 +490,8 @@ public class WorkspaceStateTransitionAnimation {
 
         final DragLayer dragLayer = mLauncher.getDragLayer();
         final float startAlpha = dragLayer.getBackgroundAlpha();
-        float finalAlpha = states.stateIsNormal ? 0 : mWorkspaceScrimAlpha;
+        float finalAlpha = states.stateIsNormal || states.stateIsNormalHidden ?
+                0 : mWorkspaceScrimAlpha;
 
         if (finalAlpha != startAlpha) {
             if (animated) {