Revert of Use SkLayerDrawLooper::Builder to construct SkLayerDrawLooper.

Source/platform/graphics/DrawLooper.h

+/*
+ * Copyright (C) 2013 Google Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef DrawLooper_h
+#define DrawLooper_h
+
+#include "platform/PlatformExport.h"
+#include "wtf/Noncopyable.h"
+#include "wtf/RefPtr.h"
+
+class SkDrawLooper;
+class SkLayerDrawLooper;
+
+namespace WebCore {
+
+class Color;
+class FloatSize;
+
+class PLATFORM_EXPORT DrawLooper {
+    // Implementing the copy constructor properly would require writing code to
+    // copy the underlying SkDrawLooper.
+    WTF_MAKE_NONCOPYABLE(DrawLooper);
+
+public:
+    enum ShadowTransformMode {
+        ShadowRespectsTransforms,
+        ShadowIgnoresTransforms
+    };
+    enum ShadowAlphaMode {
+        ShadowRespectsAlpha,
+        ShadowIgnoresAlpha
+    };
+
+    DrawLooper();
+    ~DrawLooper();
+
+    // Callees should not modify this looper other than to iterate over it.
+    // A downcast to SkLayerDrawLooper* is tantamount to a const_cast.
+    SkDrawLooper* skDrawLooper() const;
+
+    void addUnmodifiedContent();
+    void addShadow(const FloatSize& offset, float blur, const Color&,
+        ShadowTransformMode = ShadowRespectsTransforms,
+        ShadowAlphaMode = ShadowRespectsAlpha);
+
+private:
+    RefPtr<SkLayerDrawLooper> m_skDrawLooper;
+};
+
+} // namespace WebCore
+
+#endif // DrawLooper_h