Fix up all the easy virtual ... SK_OVERRIDE cases.

src/effects/SkAlphaThresholdFilter.cpp

Index: src/effects/SkAlphaThresholdFilter.cpp
diff --git a/src/effects/SkAlphaThresholdFilter.cpp b/src/effects/SkAlphaThresholdFilter.cpp
index 791d1fee1c0f496c74356fd5113fe44f97be2c07..ab84a0cb726b236f19d751012d0d26ca973d0f58 100644
--- a/src/effects/SkAlphaThresholdFilter.cpp
+++ b/src/effects/SkAlphaThresholdFilter.cpp
@@ -20,7 +20,7 @@ public:
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl)
 
 protected:
-    virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
+    void flatten(SkWriteBuffer&) const SK_OVERRIDE;
 
     virtual bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
                                SkBitmap* result, SkIPoint* offset) const SK_OVERRIDE;
@@ -71,14 +71,14 @@ public:
 
     virtual ~AlphaThresholdEffect() {};
 
-    virtual const char* name() const SK_OVERRIDE { return "Alpha Threshold"; }
+    const char* name() const SK_OVERRIDE { return "Alpha Threshold"; }
 
     float innerThreshold() const { return fInnerThreshold; }
     float outerThreshold() const { return fOuterThreshold; }
 
-    virtual void getGLProcessorKey(const GrGLCaps&, GrProcessorKeyBuilder*) const SK_OVERRIDE;
+    void getGLProcessorKey(const GrGLCaps&, GrProcessorKeyBuilder*) const SK_OVERRIDE;
 
-    virtual GrGLFragmentProcessor* createGLInstance() const SK_OVERRIDE;
+    GrGLFragmentProcessor* createGLInstance() const SK_OVERRIDE;
 
 private:
     AlphaThresholdEffect(GrTexture* texture,
@@ -102,9 +102,9 @@ private:
         this->addTextureAccess(&fMaskTextureAccess);
     }
 
-    virtual bool onIsEqual(const GrFragmentProcessor&) const SK_OVERRIDE;
+    bool onIsEqual(const GrFragmentProcessor&) const SK_OVERRIDE;
 
-    virtual void onComputeInvariantOutput(GrInvariantOutput* inout) const SK_OVERRIDE;
+    void onComputeInvariantOutput(GrInvariantOutput* inout) const SK_OVERRIDE;
 
     GR_DECLARE_FRAGMENT_PROCESSOR_TEST;
 
@@ -129,7 +129,7 @@ public:
                           const TransformedCoordsArray&,
                           const TextureSamplerArray&) SK_OVERRIDE;
 
-    virtual void setData(const GrGLProgramDataManager&, const GrProcessor&) SK_OVERRIDE;
+    void setData(const GrGLProgramDataManager&, const GrProcessor&) SK_OVERRIDE;
 
 private: