Handle odd data lengths in UTF-16 decoder

Source/wtf/text/TextCodec.h

 /*
  * Copyright (C) 2004, 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov <ap@nypop.com>
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 38 matching lines @@
     EntitiesForUnencodables,
 
     // Encodes the character as en entity as above, but escaped
     // non-alphanumeric characters. This is used in URLs.
     // For example, U+6DE would be "%26%231758%3B".
     URLEncodedEntitiesForUnencodables
 };
 
 typedef char UnencodableReplacementArray[32];
 
+enum FlushBehavior {
+    // More bytes are coming, don't flush the codec.
+    DoNotFlush = 0,
+
+    // A fetch has hit EOF. Some codecs handle fetches differently, for compat reasons.
+    FetchEOF,
+
+    // Do a full flush of the codec.
+    DataEOF
+};
+
+COMPILE_ASSERT(!DoNotFlush, DoNotFlush_is_falsy);
+COMPILE_ASSERT(FetchEOF, FetchEOF_is_truthy);
+COMPILE_ASSERT(DataEOF, DataEOF_is_truthy);
+
+
 class TextCodec {
     WTF_MAKE_NONCOPYABLE(TextCodec); WTF_MAKE_FAST_ALLOCATED;
 public:
     TextCodec() { }
     virtual ~TextCodec();
 
-    String decode(const char* str, size_t length, bool flush = false)
+    String decode(const char* str, size_t length, FlushBehavior flush = DoNotFlush)
     {
         bool ignored;
         return decode(str, length, flush, false, ignored);
     }
 
-    virtual String decode(const char*, size_t length, bool flush, bool stopOnError, bool& sawError) = 0;
+    virtual String decode(const char*, size_t length, FlushBehavior, bool stopOnError, bool& sawError) = 0;
     virtual CString encode(const UChar*, size_t length, UnencodableHandling) = 0;
     virtual CString encode(const LChar*, size_t length, UnencodableHandling) = 0;
 
     // Fills a null-terminated string representation of the given
     // unencodable character into the given replacement buffer.
     // The length of the string (not including the null) will be returned.
     static int getUnencodableReplacement(unsigned codePoint, UnencodableHandling, UnencodableReplacementArray);
 };
 
 typedef void (*EncodingNameRegistrar)(const char* alias, const char* name);
 
 typedef PassOwnPtr<TextCodec> (*NewTextCodecFunction)(const TextEncoding&, const void* additionalData);
 typedef void (*TextCodecRegistrar)(const char* name, NewTextCodecFunction, const void* additionalData);
 
 } // namespace WTF
 
 using WTF::TextCodec;
 
 #endif // TextCodec_h