use Make instead of Create to return a shared shader

include/core/SkShader.h

Index: include/core/SkShader.h
diff --git a/include/core/SkShader.h b/include/core/SkShader.h
index 828467fec237ee07e8d086945d85049827e6c55f..5d90004fa65f647065fcb03abbb46357f39c9f9e 100644
--- a/include/core/SkShader.h
+++ b/include/core/SkShader.h
@@ -23,6 +23,8 @@ class SkXfermode;
 class GrContext;
 class GrFragmentProcessor;
 
+//#define SK_SUPPORT_LEGACY_CREATESHADER_PTR
+
 /** \class SkShader
  *
  *  Shaders specify the source color(s) for what is being drawn. If a paint
@@ -335,15 +337,35 @@ public:
     /**
      *  Call this to create a new "empty" shader, that will not draw anything.
      */
-    static SkShader* CreateEmptyShader();
+    static sk_sp<SkShader> MakeEmptyShader();
 
     /**
      *  Call this to create a new shader that just draws the specified color. This should always
      *  draw the same as a paint with this color (and no shader).
      */
-    static SkShader* CreateColorShader(SkColor);
+    static sk_sp<SkShader> MakeColorShader(SkColor);
+
+    static sk_sp<SkShader> MakeComposeShader(sk_sp<SkShader> dst, sk_sp<SkShader> src,
+                                             SkXfermode::Mode);
 
-    static SkShader* CreateComposeShader(SkShader* dst, SkShader* src, SkXfermode::Mode);
+#ifdef SK_SUPPORT_LEGACY_CREATESHADER_PTR

[mtklein, 2016/03/08 14:49:11]

Wanna make it one more step general to cover all Create methods?

SK_SUPPORT_LEGACY_CREATE_METHODS ?

[reed1, 2016/03/08 15:15:19]

Could. My thought had been that the effort was so large, we might like to have
manageable subpieces (e.g. shaders, xfermodes, images) we could complete
separately, so multiple build flags might be better. Just a thought.

+    static SkShader* CreateEmptyShader() { return MakeEmptyShader().release(); }
+    static SkShader* CreateColorShader(SkColor c) { return MakeColorShader(c).release(); }
+    static SkShader* CreateComposeShader(SkShader* dst, SkShader* src, SkXfermode::Mode mode) {
+        return MakeComposeShader(dst, src, mode).release();
+    }
+    static SkShader* CreateComposeShader(SkShader* dst, SkShader* src, SkXfermode* xfer) {
+        return MakeComposeShader(dst, src, xfer).release();
+    }
+    static SkShader* CreateBitmapShader(const SkBitmap& src, TileMode tmx, TileMode tmy,
+                                        const SkMatrix* localMatrix = nullptr) {
+        return MakeBitmapShader(src, tmx, tmy, localMatrix).release();
+    }
+    static SkShader* CreatePictureShader(const SkPicture* src, TileMode tmx, TileMode tmy,
+                                         const SkMatrix* localMatrix, const SkRect* tile) {
+        return MakePictureShader(src, tmx, tmy, localMatrix, tile).release();
+    }
+#endif
 
     /**
      *  Create a new compose shader, given shaders dst, src, and a combining xfermode mode.
@@ -353,7 +375,8 @@ public:
      *  Ownership of the shaders, and the xfermode if not null, is not transfered, so the caller

[f(malita), 2016/03/08 15:50:35]

Is the ownership comment still useful?

[reed1, 2016/03/08 20:17:15]

Nope. Will remove.

      *  is still responsible for managing its reference-count for those objects.
      */
-    static SkShader* CreateComposeShader(SkShader* dst, SkShader* src, SkXfermode* xfer);
+    static sk_sp<SkShader> MakeComposeShader(sk_sp<SkShader> dst, sk_sp<SkShader> src,
+                                             SkXfermode* xfer);
 
     /** Call this to create a new shader that will draw with the specified bitmap.
      *
@@ -369,9 +392,8 @@ public:
      *  @param tmy  The tiling mode to use when sampling the bitmap in the y-direction.
      *  @return     Returns a new shader object. Note: this function never returns null.
     */
-    static SkShader* CreateBitmapShader(const SkBitmap& src,
-                                        TileMode tmx, TileMode tmy,
-                                        const SkMatrix* localMatrix = NULL);
+    static sk_sp<SkShader> MakeBitmapShader(const SkBitmap& src, TileMode tmx, TileMode tmy,
+                                            const SkMatrix* localMatrix = nullptr);
 
     // NOTE: You can create an SkImage Shader with SkImage::newShader().
 
@@ -389,10 +411,8 @@ public:
      *              bounds.
      *  @return     Returns a new shader object. Note: this function never returns null.
     */
-    static SkShader* CreatePictureShader(const SkPicture* src,
-                                         TileMode tmx, TileMode tmy,
-                                         const SkMatrix* localMatrix,
-                                         const SkRect* tile);
+    static sk_sp<SkShader> MakePictureShader(const SkPicture* src, TileMode tmx, TileMode tmy,
+                                             const SkMatrix* localMatrix, const SkRect* tile);
 
     /**
      *  If this shader can be represented by another shader + a localMatrix, return that shader