Revert of TextRun::length() should return an unsigned

Source/platform/text/TextRun.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2006, 2007, 2011 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 154 matching lines @@
     }
 
     UChar operator[](unsigned i) const { ASSERT_WITH_SECURITY_IMPLICATION(i < m_len); return is8Bit() ? m_data.characters8[i] :m_data.characters16[i]; }
     const LChar* data8(unsigned i) const { ASSERT_WITH_SECURITY_IMPLICATION(i < m_len); ASSERT(is8Bit()); return &m_data.characters8[i]; }
     const UChar* data16(unsigned i) const { ASSERT_WITH_SECURITY_IMPLICATION(i < m_len); ASSERT(!is8Bit()); return &m_data.characters16[i]; }
 
     const LChar* characters8() const { ASSERT(is8Bit()); return m_data.characters8; }
     const UChar* characters16() const { ASSERT(!is8Bit()); return m_data.characters16; }
 
     bool is8Bit() const { return m_is8Bit; }
-    unsigned length() const { return m_len; }
-    unsigned charactersLength() const { return m_charactersLength; }
+    int length() const { return m_len; }
+    int charactersLength() const { return m_charactersLength; }
 
     bool normalizeSpace() const { return m_normalizeSpace; }
     void setNormalizeSpace(bool normalizeSpace) { m_normalizeSpace = normalizeSpace; }
 
     void setText(const LChar* c, unsigned len) { m_data.characters8 = c; m_len = len; m_is8Bit = true;}
     void setText(const UChar* c, unsigned len) { m_data.characters16 = c; m_len = len; m_is8Bit = false;}
     void setText(const String&);
     void setCharactersLength(unsigned charactersLength) { m_charactersLength = charactersLength; }
 
     float horizontalGlyphStretch() const { return m_horizontalGlyphStretch; }
@@ skipping 21 matching lines @@
     void setDirectionalOverride(bool override) { m_directionalOverride = override; }
     void setCharacterScanForCodePath(bool scan) { m_characterScanForCodePath = scan; }
     void setUseComplexCodePath(bool useComplex) { m_useComplexCodePath = useComplex; }
 
     class RenderingContext : public RefCounted<RenderingContext> {
     public:
         virtual ~RenderingContext() { }
 
         virtual GlyphData glyphDataForCharacter(const Font&, const TextRun&, SimpleShaper&, UChar32 character, bool mirror, int currentCharacter, unsigned& advanceLength) = 0;
         virtual void drawSVGGlyphs(GraphicsContext*, const TextRun&, const SimpleFontData*, const GlyphBuffer&, int from, int to, const FloatPoint&) const = 0;
-        virtual float floatWidthUsingSVGFont(const Font&, const TextRun&, unsigned& charsConsumed, Glyph& glyphId) const = 0;
+        virtual float floatWidthUsingSVGFont(const Font&, const TextRun&, int& charsConsumed, Glyph& glyphId) const = 0;
     };
 
     RenderingContext* renderingContext() const { return m_renderingContext.get(); }
     void setRenderingContext(PassRefPtr<RenderingContext> context) { m_renderingContext = context; }
 
 private:
     union {
         const LChar* characters8;
         const UChar* characters16;
     } m_data;
@@ skipping 29 matching lines @@
 // Container for parameters needed to paint TextRun.
 struct TextRunPaintInfo {
     explicit TextRunPaintInfo(const TextRun& r)
         : run(r)
         , from(0)
         , to(r.length())
     {
     }
 
     const TextRun& run;
-    unsigned from;
-    unsigned to;
+    int from;
+    int to;
     FloatRect bounds;
 };
 
 }
 #endif