Add contextual types infer

src/compiler/checker.ts

@@ -22365,6 +22365,8 @@ namespace ts {
                     return contextSensitive === true ? getTypeOfExpression(left) : contextSensitive;
                 case SyntaxKind.BarBarToken:
                 case SyntaxKind.QuestionQuestionToken:
+                case SyntaxKind.BarBarEqualsToken:
+                case SyntaxKind.QuestionQuestionEqualsToken:
                     // When an || expression has a contextual type, the operands are contextually typed by that type, except
                     // when that type originates in a binding pattern, the right operand is contextually typed by the type of
                     // the left operand. When an || expression has no contextual type, the right operand is contextually typed

tests/cases/conformance/esnext/logicalAssignment/logicalAssignment5.ts

@@ -0,0 +1,7 @@
+// @strict: true
+// @target: esnext, es2020, es2015
+
+function foo (f: (a: number) => void | undefined) {
+    f ??= (a => a++)
+    f ||= (a => a++)
+}