Change ZipInputStream to use its own IsEntryCompressionMethodSupported function rather than the one in ZipEntry.

Author: Numpsy

src/ICSharpCode.SharpZipLib/Zip/ZipInputStream.cs

@@ -131,10 +131,21 @@ public bool CanDecompressEntry
 		{
 			get
 			{
-				return (entry != null) && entry.CanDecompress;
+				return (entry != null) && IsEntryCompressionMethodSupported(entry) && entry.CanDecompress;
 			}
 		}
 
+		/// <summary>
+		/// Is the compression method for the specified entry supported?
+		/// </summary>
+		/// <param name="entry"></param>
+		/// <returns></returns>
+		private static bool IsEntryCompressionMethodSupported(ZipEntry entry)
+		{
+			return entry.CompressionMethod == CompressionMethod.Deflated ||
+				   entry.CompressionMethod == CompressionMethod.Stored;
+		}
+
 		/// <summary>
 		/// Advances to the next entry in the archive
 		/// </summary>
@@ -271,7 +282,7 @@ public ZipEntry GetNextEntry()
 			}
 
 			// Determine how to handle reading of data if this is attempted.
-			if (entry.IsCompressionMethodSupported())
+			if (IsEntryCompressionMethodSupported(entry))
 			{
 				internalReader = new ReadDataHandler(InitialRead);
 			}