Ensure cursor drag is suppressed during selection drag

Once a selection drag starts, the cursor drag logic should be
skipped (short-circuited) until the selection drag ends.

Bug: 143852764, 146811252
Test: Manual and unit tests
  atest FrameworksCoreTests:EditorCursorDragTest

Change-Id: I8da82d5c197d8dcaa8d407ae11fac9a5b8521949