Update properties

Author: gugavaro

build-tools/Xamarin.Android.Tools.BootstrapTasks/Xamarin.Android.Tools.BootstrapTasks/CheckApiCompatibility.cs

@@ -194,6 +194,10 @@ Dictionary<string, HashSet<string>> LoadIssues (string content) {
 			var lines = content.Split ('\n');
 			foreach (var line in lines) {
 
+				if (string.IsNullOrWhiteSpace (line)) {
+					continue;
+				}
+
 				// Create hashset per assembly
 				if (line.StartsWith ("Compat issues with assembly", StringComparison.InvariantCultureIgnoreCase)) {
 					currentSet = new HashSet<string> ();

src/Mono.Android/Mono.Android.csproj

@@ -373,20 +373,24 @@
       <ReferenceOutputAssembly>False</ReferenceOutputAssembly>
     </ProjectReference>
   </ItemGroup>
+  <PropertyGroup>
+    <ApiCompatibilityDir>../../external/xamarin-android-api-compatibility</ApiCompatibilityDir>
+  </PropertyGroup>
   <ItemGroup>
-    <ApiCompatibilityReferenceFiles Include="../../external/xamarin-android-api-compatibility/reference/*.dll" />
+    <ApiCompatibilityFiles Include="$(ApiCompatibilityDir)/v*.txt" />
+    <ApiCompatibilityFiles Include="$(ApiCompatibilityDir)/reference/*.dll" />
   </ItemGroup>
-  <Target Name="AfterBuild" Inputs="$(TargetPath);@(ApiCompatibilityFiles)" Outputs="$(IntermediateOutputPath)/CheckApiCompatibility.stamp">
+  <Target Name="AfterBuild" Inputs="$(TargetPath);@(ApiCompatibilityFiles)" Outputs="$(IntermediateOutputPath)CheckApiCompatibility.stamp">
     <CheckApiCompatibility
       ApiCompatPath="../../packages/Microsoft.DotNet.ApiCompat.5.0.0-beta.19554.1/tools/net472/"
       ApiLevel="$(AndroidFrameworkVersion)"
       LastStableApiLevel="$(AndroidLatestStableFrameworkVersion)"
-      ApiCompatContractPath = "../../external/xamarin-android-api-compatibility/"
+      ApiCompatContractPath = "$(ApiCompatibilityDir)"
       TargetImplementationPath="$(OutputPath)"
       />
-      <Touch Files="$(IntermediateOutputPath)/CheckApiCompatibility.stamp" AlwaysCreate="True" />
+      <Touch Files="$(IntermediateOutputPath)CheckApiCompatibility.stamp" AlwaysCreate="True" />
       <ItemGroup>
-        <FileWrites Include="$(IntermediateOutputPath)/CheckApiCompatibility.stamp" />
+        <FileWrites Include="$(IntermediateOutputPath)CheckApiCompatibility.stamp" />
       </ItemGroup>
   </Target>
 </Project>