Environment
Provide version numbers for the following components (information can be retrieved by running tns info in your project folder or by inspecting the package.json of the project):
✔ Component nativescript has 4.2.4 version and is up to date.
✔ Component tns-core-modules has 4.2.1 version and is up to date.
✔ Component tns-android has 4.2.0 version and is up to date.
✔ Component tns-ios has 4.2.0 version and is up to date.

• Plugin(s): none

Describe the bug
A simple webview with an image in a local folder is not loaded on an iOS device, but is loaded on an iOS simulator and on Android devices and simulator.

To Reproduce
Create a webview, include an tag and set the src= property to a local folder, i.e,
<img src="./marker_r.png" >

An external image will display properly on an iOS device, a local image will not.

Expected behavior
Image is shown as it is on Android and an iOS simulator

Sample project
https://play.nativescript.org/?template=play-js&id=2Jslpt&v=7
(Note that playground project does not include image file in local folder, but does show what attempts have failed)

Additional context
This appears to be identical to #4443 but yet the problem persists with the latest NativeScript code.

Also posted at https://stackoverflow.com/questions/52712839/img-in-webview-works-on-ios-emulator-fails-on-ios-device