SkNonCopyable should be used with private inheritance.

include/core/SkBitmap.h

Index: include/core/SkBitmap.h
diff --git a/include/core/SkBitmap.h b/include/core/SkBitmap.h
index 18c467995030208220e7ae33032aec8947531e7c..45b6288b2ad0a90ed9d93e90db9a575352d9e00e 100644
--- a/include/core/SkBitmap.h
+++ b/include/core/SkBitmap.h
@@ -811,7 +811,7 @@ private:
     friend struct SkBitmapProcState;
 };
 
-class SkAutoLockPixels : public SkNoncopyable {
+class SkAutoLockPixels : SkNoncopyable {
 public:
     SkAutoLockPixels(const SkBitmap& bm, bool doLock = true) : fBitmap(bm) {
         fDidLock = doLock;
@@ -835,7 +835,7 @@ private:
 /** Helper class that performs the lock/unlockColors calls on a colortable.
     The destructor will call unlockColors(false) if it has a bitmap's colortable
 */
-class SkAutoLockColors : public SkNoncopyable {
+class SkAutoLockColors : SkNoncopyable {
 public:
     /** Initialize with no bitmap. Call lockColors(bitmap) to lock bitmap's
         colortable