Fix compilation error when building with clang on Linux.

src/effects/gradients/SkGradientShader.cpp

 /*
  * 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.
  */
 
 #include "SkGradientShaderPriv.h"
 #include "SkLinearGradient.h"
 #include "SkRadialGradient.h"
@@ skipping 466 matching lines @@
             b += db;
         } while (--count != 0);
     }
 }
 
 static inline int SkFixedToFFFF(SkFixed x) {
     SkASSERT((unsigned)x <= SK_Fixed1);
     return x - (x >> 16);
 }
 
-static inline U16CPU bitsTo16(unsigned x, const unsigned bits) {
-    SkASSERT(x < (1U << bits));
-    if (6 == bits) {
-        return (x << 10) | (x << 4) | (x >> 2);
-    }
-    if (8 == bits) {
-        return (x << 8) | x;
-    }
-    sk_throw();
-    return 0;
-}
-
 const uint16_t* SkGradientShaderBase::GradientShaderCache::getCache16() {
     SkOnce(&fCache16Inited, &fCache16Mutex, SkGradientShaderBase::GradientShaderCache::initCache16,
            this);
     SkASSERT(fCache16);
     return fCache16;
 }
 
 void SkGradientShaderBase::GradientShaderCache::initCache16(GradientShaderCache* cache) {
     // double the count for dither entries
     const int entryCount = kCache16Count * 2;
@@ skipping 652 matching lines @@
             (*stops)[i] = stop;
             stop = i < outColors - 1 ? stop + random->nextUScalar1() * (1.f - stop) : 1.f;
         }
     }
     *tm = static_cast<SkShader::TileMode>(random->nextULessThan(SkShader::kTileModeCount));
 
     return outColors;
 }
 
 #endif