initial preroll api

src/core/SkPictureShader.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkPictureShader.h"
 
 #include "SkBitmap.h"
@@ skipping 203 matching lines @@
 }
 
 SkShader::Context* SkPictureShader::onCreateContext(const ContextRec& rec, void* storage) const {
     SkAutoTUnref<SkShader> bitmapShader(this->refBitmapShader(*rec.fMatrix, rec.fLocalMatrix));
     if (NULL == bitmapShader.get()) {
         return NULL;
     }
     return PictureShaderContext::Create(storage, *this, rec, bitmapShader);
 }
 
+void SkPictureShader::onPreroll() const {
+    fPicture->preroll(NULL, NULL, NULL, NULL);
+}
+
 /////////////////////////////////////////////////////////////////////////////////////////
 
 SkShader::Context* SkPictureShader::PictureShaderContext::Create(void* storage,
                    const SkPictureShader& shader, const ContextRec& rec, SkShader* bitmapShader) {
     PictureShaderContext* ctx = SkNEW_PLACEMENT_ARGS(storage, PictureShaderContext,
                                                      (shader, rec, bitmapShader));
     if (NULL == ctx->fBitmapShaderContext) {
         ctx->~PictureShaderContext();
         ctx = NULL;
     }
@@ skipping 67 matching lines @@
     return bitmapShader->asFragmentProcessor(context, paint, viewM, NULL, paintColor, fp);
 }
 #else
 bool SkPictureShader::asFragmentProcessor(GrContext*, const SkPaint&, const SkMatrix&,
                                           const SkMatrix*, GrColor*,
                                           GrFragmentProcessor**) const {
     SkDEBUGFAIL("Should not call in GPU-less build");
     return false;
 }
 #endif