SkNonCopyable should be used with private inheritance.

src/core/SkMatrixClipStateMgr.h

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #ifndef SkMatrixClipStateMgr_DEFINED
 #define SkMatrixClipStateMgr_DEFINED
 
 #include "SkCanvas.h"
@@ skipping 35 matching lines @@
 
 // The SkMatrixClipStateMgr works by intercepting all the save*, restore, clip*,
 // and matrix calls sent to SkCanvas in order to track the current matrix/clip
 // state. All the other canvas calls get funnelled into a generic "call" entry
 // point that signals that a state block is required.
 class SkMatrixClipStateMgr {
 public:
     static const int32_t kIdentityWideOpenStateID = 0;
     static const int kIdentityMatID = 0;
 
-    class MatrixClipState : public SkNoncopyable {
+    class MatrixClipState : SkNoncopyable {
     public:
         class MatrixInfo {
         public:
             void reset() {
                 fMatrixID = kIdentityMatID;
                 fMatrix.reset();
             }
 
             void preTranslate(SkScalar dx, SkScalar dy) {
                 fMatrixID = -1;
@@ skipping 34 matching lines @@
                 return fMatrixID;
             }
 
         private:
             SkMatrix fMatrix;
             int      fMatrixID;
 
             typedef SkNoncopyable INHERITED;
         };
 
-        class ClipInfo : public SkNoncopyable {
+        class ClipInfo : SkNoncopyable {
         public:
             ClipInfo() {}
 
             bool clipRect(const SkRect& rect,
                           SkRegion::Op op,
                           bool doAA,
                           int matrixID) {
                 ClipOp* newClip = fClips.append();
                 newClip->fClipType = kRect_ClipType;
                 newClip->fGeom.fRRect.setRect(rect);   // storing the clipRect in the RRect
@@ skipping 283 matching lines @@
 #ifdef SK_DEBUG
     int fActualDepth;
 #endif
 
     // save layers are nested within a specific MC state. This stack tracks
     // the nesting MC state's ID as save layers are pushed and popped.
     SkTDArray<int> fStateIDStack;
 };
 
 #endif