remove device::clear -- no longer called

include/core/SkDevice.h

Index: include/core/SkDevice.h
diff --git a/include/core/SkDevice.h b/include/core/SkDevice.h
index dc5e32bffd993980f08fd82f8127bc0e1f9ab6d2..fbb53397abc4b43195445073305f6c91db9391c4 100644
--- a/include/core/SkDevice.h
+++ b/include/core/SkDevice.h
@@ -161,6 +161,7 @@ protected:
      virtual void setMatrixClip(const SkMatrix&, const SkRegion&,
                                 const SkClipStack&) {};
 
+#ifdef SK_SUPPORT_LEGACY_DEVICE_CLEAR
 private:
     /** Clears the entire device to the specified color (including alpha).
      *  Ignores the clip.
@@ -168,6 +169,7 @@ private:
      */
     virtual void clear(SkColor color);
 public:
+#endif
 
     /** These are called inside the per-device-layer loop for each draw call.
      When these are called, we have already applied any saveLayer operations,