Ignore split configs when bundle config moves shared libraries to base.apk

[grendello]

Fixes: #8979

When bundle configuration uses standard settings for split configs, the per-ABI library
directory (which contains all of our DSOs/assemblies/blobs etc) will be placed in a per-ABI
split config file named split_config.{ARCH}.apk and we use the fact to optimize startup
time.

However, if a custom build config file with the following settings is found, Android bundletool
doesn't create the per-ABI split config file, and so we need to search all the files in order
to find shared libraries, assemblies/blobs etc:

{
  "optimizations": {
    "splitsConfig": {
      "splitDimension": [
        {
          "value": "ABI",
          "negate": true
        }
      ],
    }
  }
}

The presence or absence of split config files is checked in our Java startup code which will
notice that split configs are present, but will not check (for performance reasons, to avoid
string comparisons) whether the per-ABI split config is present. We, therefore, need to let
our native runtime know in some inexpensive way that the split configs should be ignored and
that the DSOs/assemblies/blobs should be searched for in the usual, non-split config, way.

Since we know at build time whether this is the case, it's best to record the fact then and
let the native runtime merely check a boolean flag instead of dynamic detection at each app
startup.

[dellis1972]

We should probably add additional code like

Assert.IsTrue (appBuilder.Install (app), $"{app.ProjectName} should install");
				RunProjectAndAssert (app, appBuilder);
				Assert.True (WaitForActivityToStart (app.PackageName, "MainActivity",
					Path.Combine (Root, appBuilder.ProjectDirectory, "logcat.log"), 30), "Activity should have started.");

To make sure the app actually installs and runs.

[grendello]

I put the run code in a separate test InstallAndRun

[dellis1972]

the AdbStartActivity method does not check if the app started. It just does a launch,
You are better off using

RunProjectAndAssert (app, appBuilder);
Assert.True (WaitForActivityToStart (app.PackageName, "MainActivity",
		Path.Combine (Root, appBuilder.ProjectDirectory, "logcat.log"), 30), "Activity should have started.");