Yet another Could not get unknown property 'ANDROID_SUPPORT_V4_VERSION' for object of type org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler

Hi, I just updated my cordova-plugin-x-socialsharing, and now Android will not build

I get the following error…

* Where:
    Build file 'D:\dev\myapp\platforms\android\build.gradle' line: 252

    * What went wrong:
    A problem occurred evaluating root project 'android'.
    > Could not get unknown property 'ANDROID_SUPPORT_V4_VERSION' for object of type org.gradle.api.internal.artifacts.dsl.dependencies.DefaultDependencyHandler.

I notice in my config.xml I now have

<plugin name="cordova-plugin-x-socialsharing" spec="^5.4.4">
        <variable name="ANDROID_SUPPORT_V4_VERSION" value="24.1.1+" />
    </plugin>

I have tried getting rid of the line <variable name="ANDROID_SUPPORT_V4_VERSION" value="24.1.1+" /> but it just comes back when I build.

I have added removed both the plugin and Android platform numerous times. Also tried some suggestions here, but nothing works.

I have no idea what to do! I cannot build my Android version any more, just because I wanted to update a plugin (as it seemed to be crashing my app on some newer devices with the older version)

Any ideas greatly appreciated