Improve setTimeout ergonomics

Author: julien-deoux

src/DOMAPI.res

@@ -9917,3 +9917,5 @@ type blobCallback = blob => unit
 type videoFrameRequestCallback = float => videoFrameCallbackMetadata => unit
 
 type frameRequestCallback = float => unit
+
+type timeoutId

src/DOMAPI/Window.res

@@ -27,22 +27,20 @@ external btoa: (window, string) => string = "btoa"
 external atob: (window, string) => string = "atob"
 
 /**
-[Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/setTimeout)
-*/
-@send
-external setTimeout: (window, ~handler: string, ~timeout: int=?) => int = "setTimeout"
+Executes a function after a delay given in milliseconds expires.
 
-/**
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/setTimeout)
 */
 @send
-external setTimeout2: (window, ~handler: unit => unit, ~timeout: int=?) => int = "setTimeout"
+external setTimeout: (window, ~handler: unit => unit, ~timeout: int=?) => timeoutId = "setTimeout"
 
 /**
+Cancels the execution of a timeout created with setTimeout.
+
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/clearTimeout)
 */
 @send
-external clearTimeout: (window, int) => unit = "clearTimeout"
+external clearTimeout: (window, timeoutId) => unit = "clearTimeout"
 
 /**
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/setInterval)

src/Global.res

@@ -260,19 +260,18 @@ external btoa: string => string = "btoa"
 external atob: string => string = "atob"
 
 /**
-[Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/setTimeout)
-*/
-external setTimeout: (~handler: string, ~timeout: int=?) => int = "setTimeout"
+Executes a function after a delay given in milliseconds expires.
 
-/**
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/setTimeout)
 */
-external setTimeout2: (~handler: unit => unit, ~timeout: int=?) => int = "setTimeout"
+external setTimeout: (~handler: unit => unit, ~timeout: int=?) => timeoutId = "setTimeout"
 
 /**
+Cancels the execution of a timeout created with setTimeout.
+
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/clearTimeout)
 */
-external clearTimeout: int => unit = "clearTimeout"
+external clearTimeout: timeoutId => unit = "clearTimeout"
 
 /**
 [Read more on MDN](https://developer.mozilla.org/docs/Web/API/Window/setInterval)