Add Dashing gpu effect for simple dashed lines

src/gpu/SkGpuDevice.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkGpuDevice.h"
 
 #include "effects/GrBicubicEffect.h"
+#include "effects/GrDashingEffect.h"
 #include "effects/GrTextureDomain.h"
 #include "effects/GrSimpleTextureEffect.h"
 
 #include "GrContext.h"
 #include "GrBitmapTextContext.h"
 #include "GrDistanceFieldTextContext.h"
 #include "GrLayerCache.h"
 #include "GrPictureUtils.h"
 
 #include "SkGrTexturePixelRef.h"
@@ skipping 391 matching lines @@
 void SkGpuDevice::drawPoints(const SkDraw& draw, SkCanvas::PointMode mode,
                              size_t count, const SkPoint pts[], const SkPaint& paint) {
     CHECK_FOR_ANNOTATION(paint);
     CHECK_SHOULD_DRAW(draw, false);
 
     SkScalar width = paint.getStrokeWidth();
     if (width < 0) {
         return;
     }
 
+    if (paint.getPathEffect() && 2 == count && SkCanvas::kLines_PointMode == mode) {
+        if (GrDashingEffect::DrawDashLine(pts, paint, this)) {
+            return;
+        }
+    }
+
     // we only handle hairlines and paints without path effects or mask filters,
     // else we let the SkDraw call our drawPath()
     if (width > 0 || paint.getPathEffect() || paint.getMaskFilter()) {
         draw.drawPoints(mode, count, pts, paint, true);
         return;
     }
 
     GrPaint grPaint;
     SkPaint2GrPaintShader(this, paint, true, &grPaint);
 
@@ skipping 1551 matching lines @@
         GrCachedLayer* layer = fContext->getLayerCache()->findLayerOrCreate(picture, i);
 
         if (NULL != layer->getTexture()) {
             fContext->unlockScratchTexture(layer->getTexture());
             layer->setTexture(NULL);
         }
     }
 
     return true;
 }