Apply configuration new variants API only when Plugins are present

[cdsap]

Issue #412 describes the issue when using AGP 7.4 and the Plugin throws:

Failed to apply plugin 'org.gradle.android.cache-fix'.
> Cannot invoke method selector() on null object

This is caused when the plugin is configuring a project without Android plugins applied.
I can reproduce the error when in the project nowinandroid I remove the apply false in the plugin definition. That means the rootProject is trying to retrieve the androidComponents:

 def androidComponents = project.extensions.findByName("androidComponents")

when they are not applied. This is a change in the AGP not reproducible in 7.3.1.

Similar to the old implementation this PR only applies the configuration when a project contains the Android plugins.

[eboudrant]

I looked also and noticed we apply the plugin using this in our root build.gradle:

subprojects { subProject ->
    apply plugin: "org.gradle.android.cache-fix"

The error probably happen because we apply it regardless it's a project with or without android plugin. We should probably fix our build script too, thanks for looking quickly at the issue!

[runningcode]

let's add a test for this as well.

[cdsap]

@runningcode added unit tests covering plugin block configuration with/wo applying the plugin by default

[daio]

It's already merged, but shouldn't the plugin also apply to modules that use com.android.test plugin?

[eboudrant]

I think it should also apply to modules with com.android.dynamic-feature plugin.

[cdsap]

@daio @eboudrant you're right.
Checking the hierarchy of the plugins:

I'm wondering if checking by com.android.base would be enough. Next week will work on this