[Mono.Android] build and reference non-PCL Java.Interop

Fixes: http://work.devdiv.io/667174
Context: dotnet/java-interop#360

Building `Java.Interop` in a similar fashion as `Mono.Android.dll`:

    <PropertyGroup>
        <NoStdLib>true</NoStdLib>
    </PropertyGroup>
    <ItemGroup>
        <Reference Include="mscorlib">
            <HintPath>$(XAInstallPrefix)xbuild-frameworks\MonoAndroid\v1.0\mscorlib.dll</HintPath>
            <Private>False</Private>
        </Reference>
        <Reference Include="System">
            <HintPath>$(XAInstallPrefix)xbuild-frameworks\MonoAndroid\v1.0\System.dll</HintPath>
            <Private>False</Private>
        </Reference>
        <Reference Include="System.Core">
            <HintPath>$(XAInstallPrefix)xbuild-frameworks\MonoAndroid\v1.0\System.Core.dll</HintPath>
            <Private>False</Private>
        </Reference>
    </ItemGroup>

Decreases the assemblies referenced in a "Hello World" Xamarin.Android
project dramatically:

    Adding assembly reference for Java.Interop, Version=0.1.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065, recursively...
        Adding assembly reference for System.Runtime, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.ComponentModel.Composition, Version=2.0.5.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, recursively...
        Adding assembly reference for System.Diagnostics.Debug, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Threading, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Collections, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Collections.Concurrent, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Reflection, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Linq.Expressions, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Reflection.Primitives, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Dynamic.Runtime, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.ObjectModel, Version=4.0.10.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Linq, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Runtime.InteropServices, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Runtime.Extensions, Version=4.1.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
        Adding assembly reference for System.Reflection.Extensions, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, recursively...
    Adding assembly reference for Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065, recursively...

Becomes:

    Adding assembly reference for Java.Interop, Version=0.1.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065, recursively...
    Adding assembly reference for Mono.Android, Version=0.0.0.0, Culture=neutral, PublicKeyToken=84e04ff9cfb79065, recursively...

And the savings in build times for "Hello World", this is the
`Rebuild` target:
- `Debug` + PCL - 8.424s
- `Release` + PCL - 13.651s
- `Debug` + *not* PCL - 4.258s
- `Release` + *not* PCL - 9.487s

*NOTE: this was a master/Debug build of Xamarin.Android*

Changes:
- `$(MSBuildThisFile)` should be an input of `_BuildJavaInterop`
- Set `$(JavaInteropProfile)` so a non-PCL version of
  `Java.Interop.dll` is built
- Make sure to copy `Java.Interop.dll` from the `DebugNet45` directory

Author: jonathanpeppers

src/Mono.Android/Mono.Android.targets

@@ -8,13 +8,14 @@
   </ItemGroup>
   <Target Name="_BuildJavaInterop"
       BeforeTargets="BeforeResolveReferences"
-      Inputs="$(JavaInteropFullPath)\src\Java.Interop\Java.Interop.csproj"
+      Inputs="$(MSBuildThisFile);$(JavaInteropFullPath)\src\Java.Interop\Java.Interop.csproj"
       Outputs="$(OutputPath)\..\v1.0\Java.Interop.dll">
     <MSBuild
         Projects="$(JavaInteropFullPath)\src\Java.Interop\Java.Interop.csproj"
+        Properties="JavaInteropProfile=Net45;XAInstallPrefix=$(XAInstallPrefix)"
     />
     <ItemGroup>
-      <Assembly Include="$(JavaInteropFullPath)\bin\$(Configuration)\*.dll*" />
+      <Assembly Include="$(JavaInteropFullPath)\bin\$(Configuration)Net45\*.dll*" />
     </ItemGroup>
     <Copy
         SourceFiles="@(Assembly)"