Reverse some V7 edits w.r.t Indexers (#970)

* reverse some V7 edits

* Update standard/classes.md

---------

Co-authored-by: Jon Skeet <[email protected]>

Author: RexJaeschke

standard/classes.md

@@ -4192,8 +4192,6 @@ The *type* of an indexer declaration specifies the element type of the indexer i
 
 > *Note*: As indexers are designed to be used in array element-like contexts, the term *element type* as defined for an array is also used with an indexer. *end note*
 
-The *formal_parameter_list* specifies the parameters of the indexer. The formal parameter list of an indexer corresponds to that of a method ([§15.6.2](classes.md#1562-method-parameters)), except that at least one parameter shall be specified, and that the `this`, `out`, and `ref` parameter modifiers are not permitted.
-
 Unless the indexer is an explicit interface member implementation, the *type* is followed by the keyword `this`. For an explicit interface member implementation, the *type* is followed by an *interface_type*, a “`.`”, and the keyword `this`. Unlike other members, indexers do not have user-defined names.
 
 The *formal_parameter_list* specifies the parameters of the indexer. The formal parameter list of an indexer corresponds to that of a method ([§15.6.2](classes.md#1562-method-parameters)), except that at least one parameter shall be specified, and that the `this`, `ref`, and `out` parameter modifiers are not permitted.
@@ -4363,7 +4361,7 @@ Indexers and properties are very similar in concept, but differ in the following
 
 Aside from these differences, all rules defined in [§15.7.3](classes.md#1573-accessors), [§15.7.5](classes.md#1575-accessibility) and [§15.7.6](classes.md#1576-virtual-sealed-override-and-abstract-accessors) apply to indexer accessors as well as to property accessors.
 
-*Note*: This replacing of property/properties with indexer/indexers when reading [§15.7.3](classes.md#1573-accessors), [§15.7.5](classes.md#1575-accessibility) and [§15.7.6](classes.md#1576-virtual-sealed-override-and-abstract-accessors) applies to defined terms as well. For example *read-write property* becomes *read-write-indexer*. *end note*
+This replacing of property/properties with indexer/indexers when reading [§15.7.3](classes.md#1573-accessors), [§15.7.5](classes.md#1575-accessibility) and [§15.7.6](classes.md#1576-virtual-sealed-override-and-abstract-accessors) applies to defined terms as well. Specifically, *read-write property* becomes ***read-write indexer***, *read-only property* becomes ***read-only indexer***, and *write-only property* becomes ***write-only indexer***.
 
 ## 15.10 Operators