Do not invoke textclassifier when dimissing the selection

Problem: When dismissing the selection by clicking the TextView,
invalidateActionModeAsync is called to ask text classifier to
generate a new smart action for the selected text. It is not necessary
because the selection is going to be dismissed.

Cause:
To update the smart action chip when a user adjusts the selection
span by dragging the selection handle, we call showFloatingToolbar()
when we get an ACTION_UP event. The problem is that we also get
an ACTION_UP event when user dismisses the seletion by clicking
the textview. In that case, we don't need to update the smart action
chip or show the floating toolbar.

Solution:
Only call ShowFloatingToolbar() when we get an ACTION_UP and also
the user is modifying the selection/insertion curosr.

Test: Added a test in TextViewIntegrationTest.
Test: Manual. Input a long phone number. Change the selection span to
select fewer digits. Click "Call" and check the prefilled number.
Test: Manual. Drag the insertion curosr(w EditText), floating toolbar is
reshown when lifting the finger.

Fixes: 169042542

Change-Id: Ic398a8521d99218b14689fe0668adc22e6b143c5