document missing method parameters

docs/api/browser-window.md

@@ -944,10 +944,23 @@ Whether the window's document has been edited.
 
 #### `win.capturePage([rect, ]callback)`
 
+* `rect` Object (optional) - The area of the page to be captured
+  * `x` Integer
+  * `y` Integer
+  * `width` Integer
+  * `height` Integer
+* `callback` Function
+
 Same as `webContents.capturePage([rect, ]callback)`.
 
 #### `win.loadURL(url[, options])`
 
+* `url` URL
+* `options` Object (optional)
+  * `httpReferrer` String - A HTTP Referrer url.
+  * `userAgent` String - A user agent originating the request.
+  * `extraHeaders` String - Extra headers separated by "\n"
+
 Same as `webContents.loadURL(url[, options])`.
 
 The `url` can be a remote address (e.g. `http://`) or a path to a local
@@ -1137,6 +1150,8 @@ events.
 
 #### `win.setContentProtection(enable)` _macOS_ _Windows_
 
+* `enable` Boolean
+
 Prevents the window contents from being captured by other apps.
 
 On macOS it sets the NSWindow's sharingType to NSWindowSharingNone.