Delete HostProtection attributes

src/mscorlib/src/Internal/Runtime/Augments/RuntimeThread.cs

@@ -47,7 +47,6 @@ private Thread AsThread()
         public bool IsBackground
         {
             get { return IsBackgroundNative(); }
-            [HostProtection(SelfAffectingThreading = true)]
             set { SetBackgroundNative(value); }
         }
 
@@ -77,7 +76,6 @@ public bool IsBackground
         public ThreadPriority Priority
         {
             get { return (ThreadPriority)GetPriorityNative(); }
-            [HostProtection(SelfAffectingThreading = true)]
             set { SetPriorityNative((int)value); }
         }
 
@@ -113,7 +111,6 @@ public ApartmentState GetApartmentState()
         ** An unstarted thread can be marked to indicate that it will host a
         ** single-threaded or multi-threaded apartment.
         =========================================================================*/
-        [HostProtection(Synchronization = true, SelfAffectingThreading = true)]
         public bool TrySetApartmentState(ApartmentState state)
         {
 #if FEATURE_COMINTEROP_APARTMENT_SUPPORT
@@ -184,10 +181,8 @@ public void DisableComObjectEagerCleanup()
         **             ThreadInterruptedException if the thread is interrupted while waiting.
         **             ThreadStateException if the thread has not been started yet.
         =========================================================================*/
-        [HostProtection(Synchronization = true, ExternalThreading = true)]
         public void Join() => JoinInternal(Timeout.Infinite);
 
-        [HostProtection(Synchronization = true, ExternalThreading = true)]
         public bool Join(int millisecondsTimeout) => JoinInternal(millisecondsTimeout);
 
         [MethodImpl(MethodImplOptions.InternalCall)]

src/mscorlib/src/Microsoft/Win32/SafeHandles/SafeLibraryHandle.cs

@@ -6,7 +6,6 @@ namespace Microsoft.Win32 {
     using Microsoft.Win32.SafeHandles;
     using System.Security.Permissions;
 
-    [HostProtectionAttribute(MayLeakOnAbort = true)]
     sealed internal class SafeLibraryHandle : SafeHandleZeroOrMinusOneIsInvalid {
         internal SafeLibraryHandle() : base(true) {}
 

src/mscorlib/src/System/Collections/ArrayList.cs

@@ -725,7 +725,6 @@ public virtual void Sort(IComparer comparer)
 
         // Returns a thread-safe wrapper around an IList.
         //
-        [HostProtection(Synchronization=true)]
         public static IList Synchronized(IList list) {
             if (list==null)
                 throw new ArgumentNullException(nameof(list));
@@ -736,7 +735,6 @@ public virtual void Sort(IComparer comparer)
 
         // Returns a thread-safe wrapper around a ArrayList.
         //
-        [HostProtection(Synchronization=true)]
         public static ArrayList Synchronized(ArrayList list) {
             if (list==null)
                 throw new ArgumentNullException(nameof(list));

src/mscorlib/src/System/Collections/Concurrent/ConcurrentDictionary.cs

@@ -40,7 +40,6 @@ namespace System.Collections.Concurrent
     [ComVisible(false)]
     [DebuggerTypeProxy(typeof(Mscorlib_DictionaryDebugView<,>))]
     [DebuggerDisplay("Count = {Count}")]
-    [HostProtection(Synchronization = true, ExternalThreading = true)]
     public class ConcurrentDictionary<TKey, TValue> : IDictionary<TKey, TValue>, IDictionary, IReadOnlyDictionary<TKey, TValue>
     {
         /// <summary>

src/mscorlib/src/System/Collections/Concurrent/ConcurrentQueue.cs

@@ -38,7 +38,6 @@ namespace System.Collections.Concurrent
     [ComVisible(false)]
     [DebuggerDisplay("Count = {Count}")]
     [DebuggerTypeProxy(typeof(SystemCollectionsConcurrent_ProducerConsumerCollectionDebugView<>))]
-    [HostProtection(Synchronization = true, ExternalThreading = true)]
     [Serializable]
     public class ConcurrentQueue<T> : IProducerConsumerCollection<T>, IReadOnlyCollection<T>
     {

src/mscorlib/src/System/Collections/Concurrent/ConcurrentStack.cs

@@ -45,7 +45,6 @@ namespace System.Collections.Concurrent
     /// </remarks>
     [DebuggerDisplay("Count = {Count}")]
     [DebuggerTypeProxy(typeof(SystemCollectionsConcurrent_ProducerConsumerCollectionDebugView<>))]
-    [HostProtection(Synchronization = true, ExternalThreading = true)]
     public class ConcurrentStack<T> : IProducerConsumerCollection<T>, IReadOnlyCollection<T>
     {
         /// <summary>

src/mscorlib/src/System/Collections/Concurrent/OrderablePartitioner.cs

@@ -61,7 +61,6 @@ namespace System.Collections.Concurrent
     /// </ol>
     /// </para>
     /// </remarks>
-    [HostProtection(Synchronization = true, ExternalThreading = true)]
     public abstract class OrderablePartitioner<TSource> : Partitioner<TSource>
     {
         /// <summary>

src/mscorlib/src/System/Collections/Concurrent/Partitioner.cs

@@ -44,7 +44,6 @@ namespace System.Collections.Concurrent
     /// </ol>
     /// </para>
     /// </remarks>
-    [HostProtection(Synchronization = true, ExternalThreading = true)]
     public abstract class Partitioner<TSource>
     {
         /// <summary>

src/mscorlib/src/System/Collections/Concurrent/PartitionerStatic.cs

@@ -69,7 +69,6 @@ public enum EnumerablePartitionerOptions
     /// thread.
     /// </para>
     /// </remarks>
-    [HostProtection(Synchronization = true, ExternalThreading = true)]
     public static class Partitioner
     {
         /// <summary>

src/mscorlib/src/System/Collections/Hashtable.cs

@@ -1046,7 +1046,6 @@ private void putEntry (bucket[] newBuckets, Object key, Object nvalue, int hashc
 
         // Returns a thread-safe wrapper for a Hashtable.
         //
-        [HostProtection(Synchronization=true)]
         public static Hashtable Synchronized(Hashtable table) {
             if (table==null)
                 throw new ArgumentNullException(nameof(table));

src/mscorlib/src/System/Collections/SortedList.cs

@@ -528,7 +528,6 @@ public virtual Object Clone()
 
         // Returns a thread-safe SortedList.
         //
-        [HostProtection(Synchronization=true)]
         public static SortedList Synchronized(SortedList list) {
             if (list==null)
                 throw new ArgumentNullException(nameof(list));

src/mscorlib/src/System/Collections/Stack.cs

@@ -189,7 +189,6 @@ public Stack(ICollection col) : this((col==null ? 32 : col.Count))
 
         // Returns a synchronized Stack.
         //
-        [HostProtection(Synchronization=true)]
         public static Stack Synchronized(Stack stack) {
             if (stack==null)
                 throw new ArgumentNullException(nameof(stack));

src/mscorlib/src/System/Diagnostics/log.cs

@@ -22,7 +22,6 @@ namespace System.Diagnostics {
    // programatically, by registry (specifics....) or environment
    // variables.
     [Serializable]
-    [HostProtection(Synchronization=true, ExternalThreading=true)]
     internal delegate void LogMessageEventHandler(LoggingLevels level, LogSwitch category, 
                                                     String message, 
                                                     StackTrace location);

src/mscorlib/src/System/IO/MemoryStream.cs

@@ -181,7 +181,6 @@ protected override void Dispose(bool disposing)
         public override void Flush() {
         }
 
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public override Task FlushAsync(CancellationToken cancellationToken) {
 
@@ -358,7 +357,6 @@ internal void InternalGetOriginAndLength(out int origin, out int length)
             return n;
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task<int> ReadAsync(Byte[] buffer, int offset, int count, CancellationToken cancellationToken)
         {
@@ -591,7 +589,6 @@ public override void CopyTo(Stream destination, int bufferSize)
 
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteAsync(Byte[] buffer, int offset, int count, CancellationToken cancellationToken)
         {

src/mscorlib/src/System/IO/Stream.cs

@@ -109,7 +109,6 @@ internal SemaphoreSlim EnsureAsyncActiveSemaphoreInitialized()
             }
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public Task CopyToAsync(Stream destination)
         {
@@ -147,14 +146,12 @@ public Task CopyToAsync(Stream destination)
             return CopyToAsync(destination, bufferSize);
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public Task CopyToAsync(Stream destination, Int32 bufferSize)
         {
             return CopyToAsync(destination, bufferSize, CancellationToken.None);
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public virtual Task CopyToAsync(Stream destination, Int32 bufferSize, CancellationToken cancellationToken)
         {
@@ -281,14 +278,12 @@ protected virtual void Dispose(bool disposing)
 
         public abstract void Flush();
 
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public Task FlushAsync()
         {
             return FlushAsync(CancellationToken.None);
         }
 
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public virtual Task FlushAsync(CancellationToken cancellationToken)
         {
@@ -303,14 +298,12 @@ protected virtual WaitHandle CreateWaitHandle()
             return new ManualResetEvent(false);
         }
 
-        [HostProtection(ExternalThreading=true)]
         public virtual IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, Object state)
         {
             Contract.Ensures(Contract.Result<IAsyncResult>() != null);
             return BeginReadInternal(buffer, offset, count, callback, state, serializeAsynchronously: false, apm: true);
         }
 
-        [HostProtection(ExternalThreading = true)]
         internal IAsyncResult BeginReadInternal(
             byte[] buffer, int offset, int count, AsyncCallback callback, Object state, 
             bool serializeAsynchronously, bool apm)
@@ -405,14 +398,12 @@ public virtual int EndRead(IAsyncResult asyncResult)
             }
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public Task<int> ReadAsync(Byte[] buffer, int offset, int count)
         {
             return ReadAsync(buffer, offset, count, CancellationToken.None);
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public virtual Task<int> ReadAsync(Byte[] buffer, int offset, int count, CancellationToken cancellationToken)
         {
@@ -451,14 +442,12 @@ private struct ReadWriteParameters // struct for arguments to Read and Write cal
 
 
 
-        [HostProtection(ExternalThreading=true)]
         public virtual IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback callback, Object state)
         {
             Contract.Ensures(Contract.Result<IAsyncResult>() != null);
             return BeginWriteInternal(buffer, offset, count, callback, state, serializeAsynchronously: false, apm: true);
         }
 
-        [HostProtection(ExternalThreading = true)]
         internal IAsyncResult BeginWriteInternal(
             byte[] buffer, int offset, int count, AsyncCallback callback, Object state, 
             bool serializeAsynchronously, bool apm)
@@ -701,7 +690,6 @@ void ITaskCompletionAction.Invoke(Task completingTask)
             bool ITaskCompletionAction.InvokeMayRunArbitraryCode { get { return true; } }
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public Task WriteAsync(Byte[] buffer, int offset, int count)
         {
@@ -710,7 +698,6 @@ public Task WriteAsync(Byte[] buffer, int offset, int count)
 
 
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public virtual Task WriteAsync(Byte[] buffer, int offset, int count, CancellationToken cancellationToken)
         {
@@ -782,7 +769,6 @@ public virtual void WriteByte(byte value)
             Write(oneByteArray, 0, 1);
         }
 
-        [HostProtection(Synchronization=true)]
         public static Stream Synchronized(Stream stream) 
         {
             if (stream==null)
@@ -928,7 +914,6 @@ public override Task FlushAsync(CancellationToken cancellationToken)
                     Task.CompletedTask;
             }
 
-            [HostProtection(ExternalThreading = true)]
             public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, Object state)
             {
                 if (!CanRead) __Error.ReadNotSupported();
@@ -945,7 +930,6 @@ public override int EndRead(IAsyncResult asyncResult)
                 return BlockingEndRead(asyncResult);
             }
 
-            [HostProtection(ExternalThreading = true)]
             public override IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback callback, Object state)
             {
                 if (!CanWrite) __Error.WriteNotSupported();
@@ -1217,7 +1201,6 @@ public override int ReadByte()
                     return _stream.ReadByte();
             }
 
-            [HostProtection(ExternalThreading=true)]
             public override IAsyncResult BeginRead(byte[] buffer, int offset, int count, AsyncCallback callback, Object state)
             {
                 bool overridesBeginRead = _stream.HasOverriddenBeginEndRead();
@@ -1271,7 +1254,6 @@ public override void WriteByte(byte b)
                     _stream.WriteByte(b);
             }
 
-            [HostProtection(ExternalThreading=true)]
             public override IAsyncResult BeginWrite(byte[] buffer, int offset, int count, AsyncCallback callback, Object state)
             {
                 bool overridesBeginWrite = _stream.HasOverriddenBeginEndWrite();

src/mscorlib/src/System/IO/StreamReader.cs

@@ -774,7 +774,6 @@ public override String ReadLine()
         }
 
         #region Task based Async APIs
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public override Task<String> ReadLineAsync()
         {
@@ -855,7 +854,6 @@ private async Task<String> ReadLineAsyncInternal()
             return GetStringAndReleaseSharedStringBuilder(sb);
         }
 
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public override Task<String> ReadToEndAsync()
         {
@@ -892,7 +890,6 @@ private async Task<String> ReadToEndAsyncInternal()
             return GetStringAndReleaseSharedStringBuilder(sb);
         }
 
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public override Task<int> ReadAsync(char[] buffer, int index, int count)
         {
@@ -1080,7 +1077,6 @@ internal override async Task<int> ReadAsyncInternal(char[] buffer, int index, in
             return charsRead;
         }
 
-        [HostProtection(ExternalThreading=true)]
         [ComVisible(false)]
         public override Task<int> ReadBlockAsync(char[] buffer, int index, int count)
         {

src/mscorlib/src/System/IO/StreamWriter.cs

@@ -395,7 +395,6 @@ public override void Write(String value)
         }
 
         #region Task based Async APIs
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteAsync(char value)
         {
@@ -457,7 +456,6 @@ public override Task WriteAsync(char value)
             _this.CharPos_Prop = charPos;
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteAsync(String value)
         {
@@ -543,7 +541,6 @@ public override Task WriteAsync(String value)
             _this.CharPos_Prop = charPos;
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteAsync(char[] buffer, int index, int count)
         {
@@ -631,7 +628,6 @@ public override Task WriteAsync(char[] buffer, int index, int count)
             _this.CharPos_Prop = charPos;
         }
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteLineAsync()
         {
@@ -654,7 +650,6 @@ public override Task WriteLineAsync()
         }
 
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteLineAsync(char value)
         {
@@ -677,7 +672,6 @@ public override Task WriteLineAsync(char value)
         }
 
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteLineAsync(String value)
         {
@@ -700,7 +694,6 @@ public override Task WriteLineAsync(String value)
         }
 
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task WriteLineAsync(char[] buffer, int index, int count)
         {
@@ -733,7 +726,6 @@ public override Task WriteLineAsync(char[] buffer, int index, int count)
         }
 
 
-        [HostProtection(ExternalThreading = true)]
         [ComVisible(false)]
         public override Task FlushAsync()
         {