Add skia::RefPtr class to wrap ref counted classes from Skia.

ui/gfx/skia_util.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/gfx/skia_util.h"
 
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkColorFilter.h"
 #include "third_party/skia/include/core/SkColorPriv.h"
 #include "third_party/skia/include/core/SkUnPreMultiply.h"
@@ skipping 29 matching lines @@
 }
 
 RectF SkRectToRectF(const SkRect& rect) {
   return RectF(SkScalarToFloat(rect.x()),
                SkScalarToFloat(rect.y()),
                SkScalarToFloat(rect.width()),
                SkScalarToFloat(rect.height()));
 }
 
 
-SkShader* CreateImageRepShader(const gfx::ImageSkiaRep& image_rep,
-                               SkShader::TileMode tile_mode,
-                               const SkMatrix& local_matrix) {
-  SkShader* shader = SkShader::CreateBitmapShader(image_rep.sk_bitmap(),
-      tile_mode, tile_mode);
+skia::RefPtr<SkShader> CreateImageRepShader(const gfx::ImageSkiaRep& image_rep,
+                                            SkShader::TileMode tile_mode,
+                                            const SkMatrix& local_matrix) {
+  skia::RefPtr<SkShader> shader = SkShader::CreateBitmapShader(
+      image_rep.sk_bitmap(), tile_mode, tile_mode);
   SkScalar scale_x = local_matrix.getScaleX();
   SkScalar scale_y = local_matrix.getScaleY();
   SkScalar bitmap_scale = SkFloatToScalar(image_rep.GetScale());
 
   // Unscale matrix by |bitmap_scale| such that the bitmap is drawn at the
   // correct density.
   // Convert skew and translation to pixel coordinates.
   // Thus, for |bitmap_scale| = 2:
   //   x scale = 2, x translation = 1 DIP,
   // should be converted to
   //   x scale = 1, x translation = 2 pixels.
   SkMatrix shader_scale = local_matrix;
   shader_scale.preScale(bitmap_scale, bitmap_scale);
   shader_scale.setScaleX(SkScalarDiv(scale_x, bitmap_scale));
   shader_scale.setScaleY(SkScalarDiv(scale_y, bitmap_scale));
 
   shader->setLocalMatrix(shader_scale);
   return shader;
 }
 
-SkShader* CreateGradientShader(int start_point,
-                               int end_point,
-                               SkColor start_color,
-                               SkColor end_color) {
+skia::RefPtr<SkShader> CreateGradientShader(int start_point,
+                                            int end_point,
+                                            SkColor start_color,
+                                            SkColor end_color) {
   SkColor grad_colors[2] = { start_color, end_color};
   SkPoint grad_points[2];
   grad_points[0].iset(0, start_point);
   grad_points[1].iset(0, end_point);
 
-  return SkGradientShader::CreateLinear(
-      grad_points, grad_colors, NULL, 2, SkShader::kRepeat_TileMode);
+  return skia::RefPtr<SkShader>(SkGradientShader::CreateLinear(
+      grad_points, grad_colors, NULL, 2, SkShader::kRepeat_TileMode));
 }
 
-SkDrawLooper* CreateShadowDrawLooper(const std::vector<ShadowValue>& shadows) {
+skia::RefPtr<SkDrawLooper> CreateShadowDrawLooper(
+    const std::vector<ShadowValue>& shadows) {
   if (shadows.empty())
     return NULL;
 
-  SkLayerDrawLooper* looper = new SkLayerDrawLooper;
+  skia::RefPtr<SkLayerDrawLooper> looper = new SkLayerDrawLooper;
 
   looper->addLayer();  // top layer of the original.
 
   SkLayerDrawLooper::LayerInfo layer_info;
   layer_info.fPaintBits |= SkLayerDrawLooper::kMaskFilter_Bit;
   layer_info.fPaintBits |= SkLayerDrawLooper::kColorFilter_Bit;
   layer_info.fColorMode = SkXfermode::kSrc_Mode;
 
   for (size_t i = 0; i < shadows.size(); ++i) {
     const ShadowValue& shadow = shadows[i];
 
     layer_info.fOffset.set(SkIntToScalar(shadow.x()),
                            SkIntToScalar(shadow.y()));
 
     // SkBlurMaskFilter's blur radius defines the range to extend the blur from
     // original mask, which is half of blur amount as defined in ShadowValue.
-    SkMaskFilter* blur_mask = SkBlurMaskFilter::Create(
+    skia::RefPtr<SkMaskFilter> blur_mask = SkBlurMaskFilter::Create(
         SkDoubleToScalar(shadow.blur() / 2),
         SkBlurMaskFilter::kNormal_BlurStyle,
         SkBlurMaskFilter::kHighQuality_BlurFlag);
-    SkColorFilter* color_filter = SkColorFilter::CreateModeFilter(
+    skia::RefPtr<SkColorFilter> color_filter = SkColorFilter::CreateModeFilter(
         shadow.color(),
         SkXfermode::kSrcIn_Mode);
 
     SkPaint* paint = looper->addLayer(layer_info);
-    SkSafeUnref(paint->setMaskFilter(blur_mask));
-    SkSafeUnref(paint->setColorFilter(color_filter));
+    paint->setMaskFilter(blur_mask.get());
+    paint->setColorFilter(color_filter.get());
   }
 
-  return looper;
+  return looper.PassAs<SkDrawLooper>();
 }
 
 bool BitmapsAreEqual(const SkBitmap& bitmap1, const SkBitmap& bitmap2) {
   void* addr1 = NULL;
   void* addr2 = NULL;
   size_t size1 = 0;
   size_t size2 = 0;
 
   bitmap1.lockPixels();
   addr1 = bitmap1.getAddr32(0, 0);
@@ skipping 26 matching lines @@
     } else {
       rgba[i + 0] = SkGetPackedR32(pixel_in);
       rgba[i + 1] = SkGetPackedG32(pixel_in);
       rgba[i + 2] = SkGetPackedB32(pixel_in);
       rgba[i + 3] = alpha;
     }
   }
 }
 
 }  // namespace gfx