Change HarfBuzzShaper to use FloatBoxExtent for glyp bounds

Source/platform/geometry/FloatBoxExtent.h

Index: Source/platform/geometry/FloatBoxExtent.h
diff --git a/Source/platform/geometry/IntRectExtent.h b/Source/platform/geometry/FloatBoxExtent.h
similarity index 60%
copy from Source/platform/geometry/IntRectExtent.h
copy to Source/platform/geometry/FloatBoxExtent.h
index 76961d19de2ac982660abf72da2fbb35ebb7cdde..309a80e88abf0da8a1ec8e7bd26b814a6f289702 100644
--- a/Source/platform/geometry/IntRectExtent.h
+++ b/Source/platform/geometry/FloatBoxExtent.h
@@ -27,16 +27,16 @@
  * SUCH DAMAGE.
  */
 
-#ifndef IntRectExtent_h
-#define IntRectExtent_h
+#ifndef FloatBoxExtent_h
+#define FloatBoxExtent_h
 
-#include "platform/geometry/LayoutRect.h"
+#include "platform/geometry/FloatRect.h"
 
 namespace WebCore {
 
-class IntRectExtent {
+class FloatBoxExtent {
 public:
-    IntRectExtent()
+    FloatBoxExtent()
         : m_top(0)
         , m_right(0)
         , m_bottom(0)
@@ -44,7 +44,7 @@ public:
     {
     }
 
-    IntRectExtent(int top, int right, int bottom, int left)
+    FloatBoxExtent(float top, float right, float bottom, float left)
         : m_top(top)
         , m_right(right)
         , m_bottom(bottom)
@@ -52,21 +52,21 @@ public:
     {
     }
 
-    int top() const { return m_top; }
-    void setTop(int top) { m_top = top; }
+    float top() const { return m_top; }
+    void setTop(float top) { m_top = top; }
 
-    int right() const { return m_right; }
-    void setRight(int right) { m_right = right; }
+    float right() const { return m_right; }
+    void setRight(float right) { m_right = right; }
 
-    int bottom() const { return m_bottom; }
-    void setBottom(int bottom) { m_bottom = bottom; }
+    float bottom() const { return m_bottom; }
+    void setBottom(float bottom) { m_bottom = bottom; }
 
-    int left() const { return m_left; }
-    void setLeft(int left) { m_left = left; }
+    float left() const { return m_left; }
+    void setLeft(float left) { m_left = left; }
 
     bool isZero() const { return !left() && !right() && !top() && !bottom(); }
 
-    void expandRect(LayoutRect& rect) const
+    void expandRect(FloatRect& rect) const
     {
         if (isZero())
             return;
@@ -75,14 +75,30 @@ public:
         rect.expand(left() + right(), top() + bottom());
     }
 
+    void unite(const FloatBoxExtent& other)
+    {
+        m_top = std::min(m_top, other.top());
+        m_right = std::max(m_right, other.right());
+        m_bottom = std::max(m_bottom, other.bottom());
+        m_left = std::min(m_left, other.left());
+    }
+
+    void unite(const FloatRect& rect)
+    {
+        m_top = std::min(m_top, rect.y());
+        m_right = std::max(m_right, rect.maxX());
+        m_bottom = std::max(m_bottom, rect.maxY());
+        m_left = std::min(m_left, rect.x());
+    }
+
 private:
-    int m_top;
-    int m_right;
-    int m_bottom;
-    int m_left;
+    float m_top;
+    float m_right;
+    float m_bottom;
+    float m_left;
 };
 
-inline bool operator==(const IntRectExtent& a, const IntRectExtent& b)
+inline bool operator==(const FloatBoxExtent& a, const FloatBoxExtent& b)
 {
     return a.top() == b.top()
         && a.right() == b.right()
@@ -90,12 +106,12 @@ inline bool operator==(const IntRectExtent& a, const IntRectExtent& b)
         && a.left() == b.left();
 }
 
-inline bool operator!=(const IntRectExtent& a, const IntRectExtent& b)
+inline bool operator!=(const FloatBoxExtent& a, const FloatBoxExtent& b)
 {
     return !(a == b);
 }
 
-inline void operator+=(IntRectExtent& a, const IntRectExtent& b)
+inline void operator+=(FloatBoxExtent& a, const FloatBoxExtent& b)
 {
     a.setTop(a.top() + b.top());
     a.setRight(a.right() + b.right());
@@ -106,4 +122,4 @@ inline void operator+=(IntRectExtent& a, const IntRectExtent& b)
 } // namespace WebCore
 
 
-#endif // IntRectExtent_h
+#endif // FloatBoxExtent_h