move SkScalarMean into its only caller, reducing out public API exposure

include/core/SkScalar.h

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkScalar_DEFINED
 #define SkScalar_DEFINED
 
@@ skipping 121 matching lines @@
 #define SkScalarFastInvert(x)   (SK_Scalar1 / (x))
 /** Returns the square root of the SkScalar
 */
 #define SkScalarSqrt(x)         sk_float_sqrt(x)
 /** Returns b to the e
 */
 #define SkScalarPow(b, e)       sk_float_pow(b, e)
 /** Returns the average of two SkScalars (a+b)/2
 */
 #define SkScalarAve(a, b)       (((a) + (b)) * 0.5f)
-/** Returns the geometric mean of two SkScalars
-*/
-#define SkScalarMean(a, b)      sk_float_sqrt((float)(a) * (b))
 /** Returns one half of the specified SkScalar
 */
 #define SkScalarHalf(a)         ((a) * 0.5f)
 
 #define SK_ScalarSqrt2          1.41421356f
 #define SK_ScalarPI             3.14159265f
 #define SK_ScalarTanPIOver8     0.414213562f
 #define SK_ScalarRoot2Over2     0.707106781f
 
 #define SkDegreesToRadians(degrees) ((degrees) * (SK_ScalarPI / 180))
@@ skipping 81 matching lines @@
     SkASSERT(n >= 0);
     for (int i = 0; i < n; ++i) {
         if (a[i] != b[i]) {
             return false;
         }
     }
     return true;
 }
 
 #endif