Remove case insensitive culture search

Author: sdmaclea

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

@@ -1149,7 +1149,6 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\HijriCalendar.Win32.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Globalization\JapaneseCalendar.Win32.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\IO\FileStream.Win32.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\Loader\AssemblyLoadContext.Windows.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\TimeZoneInfo.Win32.cs" />
   </ItemGroup>
   <ItemGroup Condition="$(TargetsWindows) and '$(EnableWinRT)' == 'true'">
@@ -1267,7 +1266,6 @@
     <Compile Include="$(MSBuildThisFileDirectory)System\IO\PersistedFiles.Names.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\PasteArguments.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\MemoryFailPoint.Unix.cs" />
-    <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\Loader\AssemblyLoadContext.Unix.cs" Condition="'$(TargetsCoreRT)' != 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Runtime\InteropServices\Marshal.Unix.cs" Condition="'$(TargetsCoreRT)' != 'true'" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Security\SecureString.Unix.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)System\Threading\Thread.Unix.cs" />

src/System.Private.CoreLib/shared/System/Runtime/Loader/AssemblyLoadContext.Unix.cs

@@ -555,6 +555,37 @@ public void Dispose()
                 }
             }
         }
+
+        private Assembly? ResolveSatelliteAssembly(AssemblyName assemblyName)
+        {
+            string? cultureName = assemblyName.CultureName;
+
+            if (cultureName == null || cultureName.Length == 0)
+                return null;
+
+            if (assemblyName.Name == null)
+                return null;
+
+            AssemblyName parentAssemblyName = new AssemblyName(assemblyName.Name);
+
+            Assembly? parentAssembly = LoadFromAssemblyName(parentAssemblyName);
+
+            if (parentAssembly == null)
+                return null;
+
+            // ResolveSatelliteAssembly should always be called on the ALC which loaded parentAssembly
+            Debug.Assert(this == GetLoadContext(parentAssembly));
+
+            string parentDirectory = Path.GetDirectoryName(parentAssembly.Location)!;
+
+            string assemblyPath = Path.Combine(parentDirectory, cultureName, $"{assemblyName.Name}.dll");
+            if (Internal.IO.File.InternalExists(assemblyPath))
+            {
+                return LoadFromAssemblyPath(assemblyPath);
+            }
+
+            return null;
+        }
     }
 
     internal sealed class DefaultAssemblyLoadContext : AssemblyLoadContext