Remove calculateStdDeviation function from Blur effect.

BUG=

Review URL: https://codereview.chromium.org/184293003

git-svn-id: svn://svn.chromium.org/blink/trunk@168507 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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

@@ -49,8 +49,6 @@ public:
     float shadowOpacity() const { return m_shadowOpacity; }
     void setShadowOpacity(float shadowOpacity) { m_shadowOpacity = shadowOpacity; }
 
-    static float calculateStdDeviation(float);
-
     virtual FloatRect mapRect(const FloatRect&, bool forward = true) OVERRIDE FINAL;
 
     virtual TextStream& externalRepresentation(TextStream&, int indention) const OVERRIDE;

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

@@ -362,10 +362,4 @@ TextStream& FEGaussianBlur::externalRepresentation(TextStream& ts, int indent) c
     return ts;
 }
 
-float FEGaussianBlur::calculateStdDeviation(float radius)
-{
-    // Blur radius represents 2/3 times the kernel size, the dest pixel is half of the radius applied 3 times
-    return max((radius * 2 / 3.f - 0.5f) / gaussianKernelFactor(), 0.f);
-}
-
 } // namespace WebCore

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

@@ -38,8 +38,6 @@ public:
     float stdDeviationY() const;
     void setStdDeviationY(float);
 
-    static float calculateStdDeviation(float);
-
     virtual FloatRect mapRect(const FloatRect&, bool forward = true) OVERRIDE FINAL;
     virtual FloatRect determineAbsolutePaintRect(const FloatRect& requestedRect) OVERRIDE;
     static void calculateKernelSize(Filter*, unsigned& kernelSizeX, unsigned& kernelSizeY, float stdX, float stdY);