Fix definite assignment in || operator

Fixes #1070

Author: jskeet

standard/variables.md

@@ -786,7 +786,7 @@ For an expression *expr* of the form:
 ```
 
 - The definite-assignment state of *v* before *expr_first* is the same as the definite-assignment state of *v* before *expr*.
-- The definite-assignment state of *v* before *expr_second* is definitely assigned if and only if the state of *v* after *expr_first* is either definitely assigned or “definitely assigned after true expression”. Otherwise, it is not definitely assigned.
+- The definite-assignment state of *v* before *expr_second* is definitely assigned if and only if the state of *v* after *expr_first* is either definitely assigned or “definitely assigned after false expression”. Otherwise, it is not definitely assigned.
 - The definite-assignment statement of *v* after *expr* is determined by:
   - If the state of *v* after *expr_first* is definitely assigned, then the state of *v* after *expr* is definitely assigned.
   - Otherwise, if the state of *v* after *expr_second* is definitely assigned, and the state of *v* after *expr_first* is “definitely assigned after true expression”, then the state of *v* after *expr* is definitely assigned.