Arithmetic operators don't work on type parameters

[vkurchatkin]

TypeScript Version: master

Code

function test<T extends number>(n: T) {
  var a = n * 1;
  var b = n - 1;
  var c = n + 1;
}

Expected behavior:

No errors

Actual behavior:

Following errors:

test.ts(4,11): error TS2362: The left-hand side of an arithmetic operation must be of type 'any', 'number' or an enum type.
test.ts(5,11): error TS2362: The left-hand side of an arithmetic operation must be of type 'any', 'number' or an enum type.
test.ts(6,11): error TS2365: Operator '+' cannot be applied to types 'T' and '1'.

[vkurchatkin]

Oops, duplicate of #15501