Add test cases for Clamp and Repeat tiles.

src/core/SkLinearBitmapPipeline.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkLinearBitmapPipeline.h"
 
 #include "SkPM4f.h"
@@ skipping 36 matching lines @@
 
 class SkLinearBitmapPipeline::PixelPlacerInterface {
 public:
     virtual ~PixelPlacerInterface() { }
     virtual void setDestination(SkPM4f* dst) = 0;
     virtual void VECTORCALL placePixel(Sk4f pixel0) = 0;
     virtual void VECTORCALL place4Pixels(Sk4f p0, Sk4f p1, Sk4f p2, Sk4f p3) = 0;
 };
 
 namespace  {
-
 // PointProcessor uses a strategy to help complete the work of the different stages. The strategy
 // must implement the following methods:
 // * processPoints(xs, ys) - must mutate the xs and ys for the stage.
 // * maybeProcessSpan(span, next) - This represents a horizontal series of pixels
 //   to work over.
 //   span - encapsulation of span.
 //   next - a pointer to the next stage.
 //   maybeProcessSpan - returns false if it can not process the span and needs to fallback to
 //                      point lists for processing.
 template<typename Strategy, typename Next>
@@ skipping 557 matching lines @@
 
 void SkLinearBitmapPipeline::shadeSpan4f(int x, int y, SkPM4f* dst, int count) {
     SkASSERT(count > 0);
     fPixelStage->setDestination(dst);
     // The count and length arguments start out in a precise relation in order to keep the
     // math correct through the different stages. Count is the number of pixel to produce.
     // Since the code samples at pixel centers, length is the distance from the center of the
     // first pixel to the center of the last pixel. This implies that length is count-1.
     fFirstStage->pointSpan(Span{SkPoint{x + 0.5f, y + 0.5f}, count - 1.0f, count});
 }