Revert of remove unused TableMaskFilter (patchset #1 id:1 of https://codereview.chromium.org/2156463002/ )

Reason for revert:
Needed for Android:

frameworks/base/core/jni/android/graphics/MaskFilter.cpp:5:10: fatal error: 'SkTableMaskFilter.h' file not found

Original issue's description:
> remove unused TableMaskFilter
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2156463002
>
> TBR=
>
> Committed: https://skia.googlesource.com/skia/+/59779ae8ce316bf8b8082ec2df1683ccd38161f1

TBR=reed@google.com
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=skia:

Review-Url: https://codereview.chromium.org/2156183002

1 files changed, 66 insertions, 0 deletions

diff --git a/include/effects/SkTableMaskFilter.h b/include/effects/SkTableMaskFilter.h
new file mode 100644
index 0000000000..757ddf2084
--- /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