Fix tiled (stitched) FETurbulence.

The legacy implementation of FETurbulence actually never generated
tile-able noise. The algorithmic problem was fixed in Skia
(https://codereview.chromium.org/332523006/), but Blink was also not
passing the tile size (filter primitive subregion) to the turbulence
shader. This change fixes the latter (small) problem.

BUG=383495
R=fmalita

Review URL: https://codereview.chromium.org/333783002

git-svn-id: svn://svn.chromium.org/blink/trunk@176121 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/LayoutTests/TestExpectations

@@ -1062,6 +1062,8 @@ crbug.com/308768 inspector/network/network-status-non-http.html [ Skip ]
 
 crbug.com/381102 inspector/sources/debugger/debugger-step-into-custom-element-callbacks.html [ Skip ]
 
+crbug.com/383495 svg/filters/feTurbulence-tiled.svg [ NeedsRebaseline ]
+
 # Started being flaky in r175790.
 crbug.com/361045 inspector/layers/tracing-layer-tree.html [ Pass Failure ]
 

third_party/WebKit/LayoutTests/svg/filters/feTurbulence-tiled.svg

+<svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"  id="svg-root" width="100%" height="100%">
+  <defs>
+    <filter id="f1" x="0%" y="0%" width="100%" height="100%">
+      <feTurbulence type="turbulence" baseFrequency="0.03" x="0" y="0" width="50" height="50" stitchTiles="stitch"/>
+      <feTile/>
+    </filter>
+  </defs>
+  <rect width="200" height="200" filter="url(#f1)"/>
+</svg>

third_party/WebKit/Source/platform/graphics/filters/FETurbulence.cpp

@@ -401,9 +401,9 @@ void FETurbulence::applySoftware()
     fillRegion(pixelArray, paintingData, 0, absolutePaintRect().height(), m_baseFrequencyX, m_baseFrequencyY);
 }
 
-SkShader* FETurbulence::createShader(const IntRect& filterRegion)
+SkShader* FETurbulence::createShader()
 {
-    const SkISize size = SkISize::Make(filterRegion.width(), filterRegion.height());
+    const SkISize size = SkISize::Make(effectBoundaries().width(), effectBoundaries().height());
     // Frequency should be scaled by page zoom, but not by primitiveUnits.
     // So we apply only the transform scale (as Filter::apply*Scale() do)
     // and not the target bounding box scale (as SVGFilter::apply*Scale()
@@ -423,7 +423,7 @@ SkShader* FETurbulence::createShader(const IntRect& filterRegion)
 
 PassRefPtr<SkImageFilter> FETurbulence::createImageFilter(SkiaImageFilterBuilder* builder)
 {
-    SkAutoTUnref<SkShader> shader(createShader(IntRect()));
+    SkAutoTUnref<SkShader> shader(createShader());
     SkImageFilter::CropRect rect = getCropRect(builder->cropOffset());
     return adoptRef(SkRectShaderImageFilter::Create(shader, &rect));
 }

third_party/WebKit/Source/platform/graphics/filters/FETurbulence.h

@@ -117,7 +117,7 @@ private:
 
     virtual void applySoftware() OVERRIDE;
     virtual PassRefPtr<SkImageFilter> createImageFilter(SkiaImageFilterBuilder*) OVERRIDE;
-    SkShader* createShader(const IntRect& filterRegion);
+    SkShader* createShader();
 
     inline void initPaint(PaintingData&);
     float noise2D(int channel, PaintingData&, StitchData&, const FloatPoint&);