Move Dictionary to shared CoreLib partition (dotnet/coreclr#14795)

Signed-off-by: dotnet-bot-corefx-mirror <dotnet-bot@microsoft.com>

Author: jkotas

src/Common/src/CoreLib/System.Private.CoreLib.Shared.projitems

@@ -53,6 +53,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\CharEnumerator.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\CLSCompliantAttribute.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\DictionaryEntry.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\Dictionary.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\ICollection.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\ICollectionDebugView.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\IComparer.cs" />
@@ -67,7 +68,9 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\IReadOnlyList.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\KeyNotFoundException.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\KeyValuePair.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\NonRandomizedStringEqualityComparer.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\Generic\List.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)System\Collections\HashHelpers.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\ICollection.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\IComparer.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Collections\IDictionary.cs" />