[docs] Update CHANGELOG.md for conditional conformance

Author: xwu

CHANGELOG.md

@@ -39,6 +39,15 @@ Swift 5.0
 Swift 4.1
 ---------
 
+* [SE-0143][]
+
+  The standard library types `Optional`, `Array`, `ArraySlice`,
+  `ContiguousArray`, `Dictionary`, `DictionaryLiteral`, `Range`, `ClosedRange`,
+  `AnyCollection`, and `CollectionOfOne` now conform to the `Hashable` protocol
+  when their element or bound types (as the case may be) conform to `Hashable`.
+  This makes synthesized `Hashable` implementations available for types that
+  include stored properties of these types.
+
 * [SE-0189][]
 
   If an initializer is declared in a different module from a struct, it must
@@ -74,12 +83,12 @@ Swift 4.1
   s[keyPath: p] // "H"
   ```
 
-* [SE-0143][] The standard library types `Optional`, `Array`, and
-	`Dictionary` now conform to the `Equatable` protocol when their element types
-	conform to `Equatable`. This allows the `==` operator to compose (e.g., one
-	can compare two values of type `[Int : [Int?]?]` with `==`), as well as use
-  various algorthims defined for `Equatable` element types, such as
-	`index(of:)`.
+* [SE-0143][] The standard library types `Optional`, `Array`, `ArraySlice`,
+  `ContiguousArray`, and `Dictionary` now conform to the `Equatable` protocol
+  when their element types conform to `Equatable`. This allows the `==` operator
+  to compose (e.g., one can compare two values of type `[Int : [Int?]?]` with
+  `==`), as well as use various algorthims defined for `Equatable` element
+  types, such as `index(of:)`.
 
 * [SE-0157][] is implemented. Associated types can now declare "recursive"
 	constraints, which require that the associated type conform to the enclosing