enforce 16byte alignment in shader contexts

src/core/SkDraw.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.
  */
 #define __STDC_LIMIT_MACROS
 
 #include "SkDraw.h"
 #include "SkBlitter.h"
@@ skipping 1680 matching lines @@
     dst[0] = verts[state.f0];
     dst[1] = verts[state.f1];
     dst[2] = verts[state.f2];
     return matrix->setPolyToPoly(src, dst, 3);
 }
 
 class SkTriColorShader : public SkShader {
 public:
     SkTriColorShader() {}
 
-    size_t contextSize(const ContextRec&) const override;
-
     class TriColorShaderContext : public SkShader::Context {
     public:
         TriColorShaderContext(const SkTriColorShader& shader, const ContextRec&);
         virtual ~TriColorShaderContext();
 
         bool setup(const SkPoint pts[], const SkColor colors[], int, int, int);
 
         void shadeSpan(int x, int y, SkPMColor dstC[], int count) override;
 
     private:
         SkMatrix    fDstToUnit;
         SkPMColor   fColors[3];
 
         typedef SkShader::Context INHERITED;
     };
 
     SK_TO_STRING_OVERRIDE()
 
     // For serialization.  This will never be called.
     Factory getFactory() const override { sk_throw(); return nullptr; }
 
 protected:
+    size_t onContextSize(const ContextRec&) const override;
     Context* onCreateContext(const ContextRec& rec, void* storage) const override {
         return new (storage) TriColorShaderContext(*this, rec);
     }
 
 private:
     typedef SkShader INHERITED;
 };
 
 bool SkTriColorShader::TriColorShaderContext::setup(const SkPoint pts[], const SkColor colors[],
                                                     int index0, int index1, int index2) {
@@ skipping 30 matching lines @@
     return static_cast<int>(SkScalarPin(v, 0, 1) * 256 + 0.5);
 }
 
 
 SkTriColorShader::TriColorShaderContext::TriColorShaderContext(const SkTriColorShader& shader,
                                                                const ContextRec& rec)
     : INHERITED(shader, rec) {}
 
 SkTriColorShader::TriColorShaderContext::~TriColorShaderContext() {}
 
-size_t SkTriColorShader::contextSize(const ContextRec&) const {
-    return sizeof(TriColorShaderContext);
+size_t SkTriColorShader::onContextSize(const ContextRec&) const {
+    return SkAlign16(sizeof(TriColorShaderContext));
 }
+
 void SkTriColorShader::TriColorShaderContext::shadeSpan(int x, int y, SkPMColor dstC[], int count) {
     const int alphaScale = Sk255To256(this->getPaintAlpha());
 
     SkPoint src;
 
     for (int i = 0; i < count; i++) {
         fDstToUnit.mapXY(SkIntToScalar(x), SkIntToScalar(y), &src);
         x += 1;
 
         int scale1 = ScalarTo256(src.fX);
@@ skipping 269 matching lines @@
         mask->fImage = SkMask::AllocImage(size);
         memset(mask->fImage, 0, mask->computeImageSize());
     }
 
     if (SkMask::kJustComputeBounds_CreateMode != mode) {
         draw_into_mask(*mask, devPath, style);
     }
 
     return true;
 }