[CSS] Accept 8 (#RRGGBBAA) and 4 (#RGBA) value hex colors

third_party/WebKit/Source/platform/graphics/Color.cpp

 /*
  * Copyright (C) 2003, 2004, 2005, 2006, 2008 Apple Inc. All rights reserved.
  *
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 101 matching lines @@
     int r = static_cast<int>(nextafter(256, 0) * (colors * (1 - c)));
     int g = static_cast<int>(nextafter(256, 0) * (colors * (1 - m)));
     int b = static_cast<int>(nextafter(256, 0) * (colors * (1 - y)));
     return makeRGBA(r, g, b, static_cast<float>(nextafter(256, 0) * a));
 }
 
 // originally moved here from the CSS parser
 template <typename CharacterType>
 static inline bool parseHexColorInternal(const CharacterType* name, unsigned length, RGBA32& rgb)
 {
-    if (length != 3 && length != 6)
+    if (length != 3 && length != 4 && length != 6 && length != 8)
         return false;
     unsigned value = 0;
     for (unsigned i = 0; i < length; ++i) {
         if (!isASCIIHexDigit(name[i]))
             return false;
         value <<= 4;
         value |= toASCIIHexValue(name[i]);
     }
     if (length == 6) {
         rgb = 0xFF000000 | value;
         return true;
     }
+    if (length == 8) {
+        // We parsed the values into RGBA order, but the RGBA32 type
+        // expects them to be in ARGB order, so we right rotate eight bits.
+        rgb = value << 24 | value >> 8;
+        return true;
+    }
+    if (length == 4) {
+        // #abcd converts to ddaabbcc in RGBA32.
+        rgb = (value & 0xF) << 28 | (value & 0xF) << 24
+            | (value & 0xF000) << 8 | (value & 0xF000) << 4
+            | (value & 0xF00) << 4 | (value & 0xF00)
+            | (value & 0xF0) | (value & 0xF0) >> 4;
+        return true;
+    }
     // #abc converts to #aabbcc
     rgb = 0xFF000000
         | (value & 0xF00) << 12 | (value & 0xF00) << 8
         | (value & 0xF0) << 8 | (value & 0xF0) << 4
         | (value & 0xF) << 4 | (value & 0xF);
     return true;
 }
 
 bool Color::parseHexColor(const LChar* name, unsigned length, RGBA32& rgb)
 {
@@ skipping 303 matching lines @@
             (color.green() * alpha  + 254) / 255,
             (color.blue() * alpha  + 254) / 255,
             alpha).rgb();
     } else
          pixelColor = color.rgb();
 
     return pixelColor;
 }
 
 } // namespace blink