Have all skia platforms share FontPlatformData::hash() implementation

Source/core/platform/graphics/skia/FontPlatformDataSkia.cpp

 /*
  * Copyright (c) 2006, 2007, 2008, Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 19 matching lines @@
 
 #include "config.h"
 #include "core/platform/graphics/FontPlatformData.h"
 
 #include "SkEndian.h"
 #include "SkTypeface.h"
 #include "core/platform/graphics/FontCache.h"
 
 namespace WebCore {
 
+#if (!ENABLE(GDI_FONTS_ON_WINDOWS) || !OS(WIN)) && !OS(MACOSX)
+unsigned FontPlatformData::hash() const
+{
+    unsigned h = SkTypeface::UniqueID(m_typeface.get());
+    h ^= 0x01010101 * ((static_cast<int>(m_orientation) << 2) | (static_cast<int>(m_fakeBold) << 1) | static_cast<int>(m_fakeItalic));
+
+    // This memcpy is to avoid a reinterpret_cast that breaks strict-aliasing
+    // rules. Memcpy is generally optimized enough so that performance doesn't
+    // matter here.
+    uint32_t textSizeBytes;
+    memcpy(&textSizeBytes, &m_textSize, sizeof(uint32_t));
+    h ^= textSizeBytes;
+
+    return h;
+}
+
+#endif
+
 #if ENABLE(OPENTYPE_VERTICAL)
 PassRefPtr<OpenTypeVerticalData> FontPlatformData::verticalData() const
 {
     return fontCache()->getVerticalData(typeface()->uniqueID(), *this);
 }
 
 PassRefPtr<SharedBuffer> FontPlatformData::openTypeTable(uint32_t table) const
 {
     RefPtr<SharedBuffer> buffer;
 
     SkFontTableTag tag = SkEndianSwap32(table);
     const size_t tableSize = m_typeface->getTableSize(tag);
     if (tableSize) {
         Vector<char> tableBuffer(tableSize);
         m_typeface->getTableData(tag, 0, tableSize, &tableBuffer[0]);
         buffer = SharedBuffer::adoptVector(tableBuffer);
     }
     return buffer.release();
 }
 #endif
 
 } // namespace WebCore