Fix issue with incremental build with globs.

Add a target that runs before CoreCompile that will record and store the
state of the Compile ItemGroup. This file is added to the
CustomAdditionalCompileInputs which is an input to CoreCompile. When this
file changes, CoreCompile will run again. This fixes the issue of deleting
a file or adding a file with an old timestamp to a glob (e.g. *.cs).

Fixes #1327

src/XMakeTasks/Microsoft.Common.CurrentVersion.targets

@@ -3010,6 +3010,7 @@ Copyright (C) Microsoft Corporation. All rights reserved.
       _GenerateCompileInputs;
       BeforeCompile;
       _TimeStampBeforeCompile;
+      _GenerateCompilerDependencyCache;
       CoreCompile;
       _TimeStampAfterCompile;
       AfterCompile;
@@ -3164,6 +3165,31 @@ Copyright (C) Microsoft Corporation. All rights reserved.
 
   </Target>
 
+  <!--
+    ============================================================
+                                        _GenerateCompilerDependencyCache
+
+    Generate a file used to track compiler dependencies between incremental build
+    executions. This handles cases where items are added or removed from a glob (e.g.
+    <Compile Include="**\*.cs" />) and can't otherwise be detected with timestamp 
+    comparisons. The file contains a hash of compiler inputs that are known to 
+    contribute to incremental build inconsistencies.
+    ============================================================
+    -->
+  <Target Name="_GenerateCompilerDependencyCache" DependsOnTargets="ResolveAssemblyReferences">
+    <ItemGroup>
+      <CustomAdditionalCompileInputs Include="$(IntermediateOutputPath)CoreCompileInputs.cache" />
+      <CoreCompileCache Include="@(Compile->'%(FullPath)')" />
+      <CoreCompileCache Include="@(ReferencePath->'%(FullPath)')" />
+    </ItemGroup>
+
+    <Hash ItemsToHash="@(CoreCompileCache)">
+      <Output TaskParameter="HashResult" PropertyName="CoreCompileDependencyHash" />
+    </Hash>
+
+    <WriteLinesToFile Lines="$(CoreCompileDependencyHash)" File="$(IntermediateOutputPath)CoreCompileInputs.cache" Overwrite="True" WriteOnlyWhenDifferent="True" />
+  </Target>
+
   <!--
     ============================================================
                                         _TimeStampAfterCompile