Focus running task in overview grid

- calculateTaskSize now returns the Rect for focused task
- Introduced calculateGridTaskSize for non-focused task, and translate non-focused tasks to fit the grid
- As Task Rect is now vertically centered, removed ClearAllButton's grid vertical translation
- When ClearAllButton is not shown (e.g. quickswitch), make sure ClearAllButton's scroll won't be used when page snapping. This happens when page scrolls are translated so they're negative.
- Added back ActionsView when task is focused below the TaskView, which become invisible as you scroll
- In Modal state, move the ActionsView down so it won't cover the TaskView

Bug: 175939487
Test: manual
Change-Id: Idfa94a51f856418adc0503cf04211dcb4b1814fe

quickstep/src/com/android/launcher3/uioverrides/RecentsViewStateController.java

@@ -103,12 +103,11 @@ public final class RecentsViewStateController extends
 
     private void setAlphas(PropertySetter propertySetter, StateAnimationConfig config,
             LauncherState state) {
-        float clearAllButtonAlpha = (state.getVisibleElements(mLauncher) & CLEAR_ALL_BUTTON) != 0
-                ? 1 : 0;
+        float clearAllButtonAlpha = state.areElementsVisible(mLauncher, CLEAR_ALL_BUTTON) ? 1 : 0;
         propertySetter.setFloat(mRecentsView.getClearAllButton(), ClearAllButton.VISIBILITY_ALPHA,
                 clearAllButtonAlpha, LINEAR);
-        float overviewButtonAlpha = (state.getVisibleElements(mLauncher) & OVERVIEW_ACTIONS) != 0
-                ? 1 : 0;
+        float overviewButtonAlpha = state.areElementsVisible(mLauncher, OVERVIEW_ACTIONS)
+                && mRecentsView.shouldShowOverviewActionsForState(state) ? 1 : 0;
         propertySetter.setFloat(mLauncher.getActionsView().getVisibilityAlpha(),
                 MultiValueAlpha.VALUE, overviewButtonAlpha, config.getInterpolator(
                         ANIM_OVERVIEW_ACTIONS_FADE, LINEAR));