Fix more warnings on linux

Source/core/platform/graphics/harfbuzz/HarfBuzzShaper.cpp

 /*
  * Copyright (c) 2012 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 56 matching lines @@
     }
 
     T* get() { return m_ptr; }
     void set(T* ptr) { m_ptr = ptr; }
 private:
     T* m_ptr;
     DestroyFunction m_destroy;
 };
 
 
-static const int cHarfBuzzCacheMaxSize = 256;
+static const unsigned cHarfBuzzCacheMaxSize = 256;
 
 struct CachedShapingResultsLRUNode;
 struct CachedShapingResults;
 typedef std::map<std::wstring, CachedShapingResults*> CachedShapingResultsMap;
 typedef std::list<CachedShapingResultsLRUNode*> CachedShapingResultsLRU;
 
 struct CachedShapingResults {
     CachedShapingResults(hb_buffer_t* harfBuzzBuffer, const Font* runFont, hb_direction_t runDir);
     ~CachedShapingResults();
 
@@ skipping 776 matching lines @@
     if (!foundToX)
         toX = m_run.rtl() ? 0 : m_totalWidth;
 
     // Using floorf() and roundf() as the same as mac port.
     if (fromX < toX)
         return FloatRect(floorf(point.x() + fromX), point.y(), roundf(toX - fromX), height);
     return FloatRect(floorf(point.x() + toX), point.y(), roundf(fromX - toX), height);
 }
 
 } // namespace WebCore