remove unneeded SkShader::validContext

include/core/SkEmptyShader.h

Index: include/core/SkEmptyShader.h
diff --git a/include/core/SkEmptyShader.h b/include/core/SkEmptyShader.h
index d1a067f432576ceb6987627537f5f478855e1eae..7de3bc1f8f9c2105681d6dde157448e5b4257335 100644
--- a/include/core/SkEmptyShader.h
+++ b/include/core/SkEmptyShader.h
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2011 Google Inc.
  *
@@ -6,13 +5,13 @@
  * found in the LICENSE file.
  */
 
-
-
 #ifndef SkEmptyShader_DEFINED
 #define SkEmptyShader_DEFINED
 
 #include "SkShader.h"
 
+// TODO: move this to private, as there is a public factory on SkShader
+
 /**
  *  \class SkEmptyShader
  *  A Shader that always draws nothing. Its createContext always returns NULL.
@@ -27,21 +26,16 @@ public:
         return sizeof(SkShader::Context);
     }
 
-    virtual bool validContext(const ContextRec&, SkMatrix* totalInverse = NULL) const SK_OVERRIDE {
-        return false;
-    }
-
-    virtual SkShader::Context* createContext(const ContextRec&, void*) const SK_OVERRIDE {
-        // validContext returns false.
-        return NULL;
-    }
-
     SK_TO_STRING_OVERRIDE()
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmptyShader)
 
 protected:
     SkEmptyShader(SkReadBuffer& buffer) : INHERITED(buffer) {}
 
+    virtual SkShader::Context* onCreateContext(const ContextRec&, void*) const SK_OVERRIDE {
+        return NULL;
+    }
+
 private:
     typedef SkShader INHERITED;
 };