Merge 0.69.4 into 1.0.

Conflicts:
	docs/content/overview/version-history.md
	src/Directory.Build.props
	src/MySqlConnector/MySqlConnection.cs

Author: bgrainger

docs/content/overview/version-history.md

@@ -27,6 +27,10 @@ Version History
 * Add `net5.0` target framework.
 * Reduce memory allocations when hashing passwords (during login).
 
+### 0.69.4
+
+* Fix connection pool leak when a failure (e.g., timeout) occurs on a connection: [#836](https://github.com/mysql-net/MySqlConnector/issues/836).
+
 ### 0.69.3
 
 * Fix `Failed to read the result set.` error when using `MySqlBulkCopy`: [#780](https://github.com/mysql-net/MySqlConnector/issues/780).

src/MySqlConnector/MySqlConnection.cs

@@ -854,9 +854,6 @@ private void VerifyNotDisposed()
 
 		private Task CloseAsync(bool changeState, IOBehavior ioBehavior)
 		{
-			if (m_connectionState == ConnectionState.Closed)
-				return Utility.CompletedTask;
-
 			// check fast path
 			if (m_activeReader is null &&
 				CurrentTransaction is null &&
@@ -924,31 +921,28 @@ private async Task DoCloseAsync(bool changeState, IOBehavior ioBehavior)
 			}
 #endif
 
-			if (m_connectionState != ConnectionState.Closed)
+			try
 			{
-				try
-				{
-					await CloseDatabaseAsync(ioBehavior, CancellationToken.None).ConfigureAwait(false);
-				}
-				finally
+				await CloseDatabaseAsync(ioBehavior, CancellationToken.None).ConfigureAwait(false);
+			}
+			finally
+			{
+				if (m_session is not null)
 				{
-					if (m_session is not null)
+					if (GetInitializedConnectionSettings().Pooling)
 					{
-						if (GetInitializedConnectionSettings().Pooling)
-						{
-							m_session.ReturnToPool();
-						}
-						else
-						{
-							await m_session.DisposeAsync(ioBehavior, CancellationToken.None).ConfigureAwait(false);
-							m_session.OwningConnection = null;
-						}
-						m_session = null;
+						m_session.ReturnToPool();
 					}
-
-					if (changeState)
-						SetState(ConnectionState.Closed);
+					else
+					{
+						await m_session.DisposeAsync(ioBehavior, CancellationToken.None).ConfigureAwait(false);
+						m_session.OwningConnection = null;
+					}
+					m_session = null;
 				}
+
+				if (changeState)
+					SetState(ConnectionState.Closed);
 			}
 		}