Re-enable AAPT2 in the Samples and the Uno Solution Template

[ghuntley]

Current behavior

We disabled AAPT2 in #1186 and #1364 because of dotnet/android#3327

Expected behavior

When VSWIN ships dotnet/android#3327 we need to re-enable AAPT2 for:

• The Android head of the SamplesApp
• The Android head generated by the Uno Solution Template

Environment

Nuget Package: master

Affected platform(s):

• iOS
• Android
• WebAssembly
• Windows
• Build tasks

Visual Studio

• 2017 (version: )
• 2019 (version: )
• for Mac (version: )

Relevant plugins

• Resharper (version: )

Anything else we need to know?

Opening as a help wanted as the complexity is low and a good candidate for someone's first pull-request to the project. The following article is a good read about the differences between AAPT1 and AAPT2: https://connortumbleson.com/2018/02/19/taking-a-look-at-aapt2/

[MatFillion]

I tried using aapt2 since dotnet/android#3327 was merged and released.
I've set <AndroidUseAapt2>true</AndroidUseAapt2> instead of false but issue still occurs.

I'm on VS2019 16.4 and Xamarin.Android 10.1.1.0.

The fix was released in VS2019 16.3 and Xamarin 10.0.0.43 according to this reply dotnet/android#3327 (comment)

We can repro with a simple "new uno app" from the app template (vsix)

[MatFillion]

Maybe the name is really invalid though, file failing is repos\App7\App7\App7.Shared\Assets\Square44x44Logo.targetsize-24_altform-unplated.png

That asset probably belongs in the UWP head and not in the shared project.