Update identifierPattern to allow deinit/subscript

Author: DougGregor

CodeGeneration/Sources/SyntaxSupport/PatternNodes.swift

@@ -57,7 +57,15 @@ public let PATTERN_NODES: [Node] = [
     children: [
       Child(
         name: "identifier",
-        kind: .token(choices: [.token(.identifier), .keyword(.self), .keyword(.`init`)])
+        kind: .token(
+          choices: [
+            .token(.identifier),
+            .keyword(.self),
+            .keyword(.`init`),
+            .keyword(.`deinit`),
+            .keyword(.`subscript`),
+          ]
+        )
       )
     ]
   ),

Sources/SwiftParser/Names.swift

@@ -66,7 +66,9 @@ extension Parser {
   mutating func parseDeclReferenceExpr(_ flags: DeclNameOptions = []) -> RawDeclReferenceExprSyntax {
     // Consume the base name.
     let base: RawTokenSyntax
-    if let identOrSelf = self.consume(if: .identifier, .keyword(.self), .keyword(.Self)) ?? self.consume(if: .keyword(.`init`)) ?? self.consume(if: .keyword(.`deinit`)) ?? self.consume(if: .keyword(.`subscript`)) {
+    if let identOrSelf = self.consume(if: .identifier, .keyword(.self), .keyword(.Self)) ?? self.consume(if: .keyword(.`init`)) ?? self.consume(
+      if: .keyword(.`deinit`)
+    ) ?? self.consume(if: .keyword(.`subscript`)) {
       base = identOrSelf
     } else if flags.contains(.operators), let (_, _) = self.at(anyIn: Operator.self) {
       base = self.consumeAnyToken(remapping: .binaryOperator)