remove unnessary overrides, as base class now does this for shaders

skia/ext/pixel_ref_utils_unittest.cc

Index: skia/ext/pixel_ref_utils_unittest.cc
diff --git a/skia/ext/pixel_ref_utils_unittest.cc b/skia/ext/pixel_ref_utils_unittest.cc
index ab8f7b0801583433e9d60d9f9821b0860b5b6cb3..237bc60e37a46dafc28d8875ce5ac4ebf715564d 100644
--- a/skia/ext/pixel_ref_utils_unittest.cc
+++ b/skia/ext/pixel_ref_utils_unittest.cc
@@ -51,13 +51,7 @@ class TestDiscardableShader : public SkShader {
     return SkShader::kDefault_BitmapType;
   }
 
-  // Pure virtual implementaiton.
-  virtual SkShader::Context* createContext(const SkBitmap& device,
-                                           const SkPaint& paint,
-                                           const SkMatrix& matrix,
-                                           void* storage) const OVERRIDE {
-    return NULL;
-  };
+  // not indended to return an actual context. Just need to supply this.
   virtual size_t contextSize() const OVERRIDE {
     return sizeof(SkShader::Context);
   }