| The left-hand side and right-hand side of this assignment are the same. It has | |
| no effect. | |
| This also handles assignments in which the right-hand side is a call to | |
| Preconditions.checkNotNull(), which returns the variable that was checked for | |
| non-nullity. If you just intended to check that the variable is non-null, please | |
| don't assign the result to the checked variable; just call | |
| Preconditions.checkNotNull() as a bare statement. |