Revert of remove unused TableMaskFilter

include/effects/SkTableMaskFilter.h

Index: include/effects/SkTableMaskFilter.h
diff --git a/include/effects/SkTableMaskFilter.h b/include/effects/SkTableMaskFilter.h
new file mode 100644
index 0000000000000000000000000000000000000000..757ddf208489df94b09a3bf3398f299d437ef4a1
--- /dev/null
+++ b/include/effects/SkTableMaskFilter.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2006 The Android Open Source Project
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkTableMaskFilter_DEFINED
+#define SkTableMaskFilter_DEFINED
+
+#include "SkMaskFilter.h"
+#include "SkScalar.h"
+
+/** \class SkTableMaskFilter
+
+    Applies a table lookup on each of the alpha values in the mask.
+    Helper methods create some common tables (e.g. gamma, clipping)
+ */
+class SK_API SkTableMaskFilter : public SkMaskFilter {
+public:
+    /** Utility that sets the gamma table
+     */
+    static void MakeGammaTable(uint8_t table[256], SkScalar gamma);
+
+    /** Utility that creates a clipping table: clamps values below min to 0
+        and above max to 255, and rescales the remaining into 0..255
+     */
+    static void MakeClipTable(uint8_t table[256], uint8_t min, uint8_t max);
+
+    static SkMaskFilter* Create(const uint8_t table[256]) {
+        return new SkTableMaskFilter(table);
+    }
+
+    static SkMaskFilter* CreateGamma(SkScalar gamma) {
+        uint8_t table[256];
+        MakeGammaTable(table, gamma);
+        return new SkTableMaskFilter(table);
+    }
+
+    static SkMaskFilter* CreateClip(uint8_t min, uint8_t max) {
+        uint8_t table[256];
+        MakeClipTable(table, min, max);
+        return new SkTableMaskFilter(table);
+    }
+
+    SkMask::Format getFormat() const override;
+    bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*) const override;
+
+    SK_TO_STRING_OVERRIDE()
+    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTableMaskFilter)
+
+protected:
+    virtual ~SkTableMaskFilter();
+
+    void flatten(SkWriteBuffer&) const override;
+
+private:
+    SkTableMaskFilter();
+    explicit SkTableMaskFilter(const uint8_t table[256]);
+
+    uint8_t fTable[256];
+
+    typedef SkMaskFilter INHERITED;
+};
+
+#endif