Some inline ARM assembly for saturated arithmetic, a small speed-up for

Source/platform/LayoutUnit.h

Index: Source/platform/LayoutUnit.h
diff --git a/Source/platform/LayoutUnit.h b/Source/platform/LayoutUnit.h
index e931ced19ca4048a14c083c604a00dbc55007c30..4f677d1dd60f97ad79948760415d97bdbe7cf79e 100644
--- a/Source/platform/LayoutUnit.h
+++ b/Source/platform/LayoutUnit.h
@@ -220,21 +220,14 @@ private:
         return ::fabs(value) <= std::numeric_limits<int>::max() / kFixedPointDenominator;
     }
 
-    inline void setValue(int value)
+    ALWAYS_INLINE void setValue(int value)
     {
-        if (value > intMaxForLayoutUnit)
-            m_value = std::numeric_limits<int>::max();
-        else if (value < intMinForLayoutUnit)
-            m_value = std::numeric_limits<int>::min();
-        else
-            m_value = value * kFixedPointDenominator;
+        m_value = saturatedSet(value, kLayoutUnitFractionalBits);
     }
+
     inline void setValue(unsigned value)
     {
-        if (value >= static_cast<unsigned>(intMaxForLayoutUnit))
-            m_value = std::numeric_limits<int>::max();
-        else
-            m_value = value * kFixedPointDenominator;
+        m_value = saturatedSet(value, kLayoutUnitFractionalBits);
     }
 
     int m_value;