Fixes up, down, spacebar and key variation keyboard actions with NestedScrollView and CoordinatorLayout.

Bug: 243555083
Test: Added tests
Change-Id: I216f42029674cc8210907eb6591dc9584b000c75

• coordinatorlayout/coordinatorlayout/build.gradle[diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/AndroidManifest.xml[diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/java/androidx/coordinatorlayout/testutils/AppBarStateChangedListener.java[Added - diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/java/androidx/coordinatorlayout/testutils/NestedScrollViewActions.java[Added - diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/java/androidx/coordinatorlayout/widget/CoordinatorLayoutKeyEventTest.java[Added - diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/java/androidx/coordinatorlayout/widget/CoordinatorWithNestedScrollViewsActivity.java[Added - diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/res/layout/activity_coordinator_with_nested_scroll_views.xml[Added - diff]
• coordinatorlayout/coordinatorlayout/src/androidTest/res/values/strings.xml[Added - diff]
• coordinatorlayout/coordinatorlayout/src/main/java/androidx/coordinatorlayout/widget/CoordinatorLayout.java[diff]
• core/core/src/androidTest/java/androidx/core/widget/NestedScrollViewWithCollapsingToolbarTest.java[diff]
• core/core/src/main/java/androidx/core/widget/NestedScrollView.java[diff]