clean up more dead code

src/utils/SkSHA1.h

-/*
- * Copyright 2013 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#ifndef SkSHA1_DEFINED
-#define SkSHA1_DEFINED
-
-#include "SkTypes.h"
-#include "SkEndian.h"
-#include "SkStream.h"
-
-//The following macros can be defined to affect the SHA1 code generated.
-//SK_SHA1_CLEAR_DATA causes all intermediate state to be overwritten with 0's.
-//SK_CPU_BENDIAN allows 32 bit <=> 8 bit conversions without copies (if alligned).
-//SK_CPU_FAST_UNALIGNED_ACCESS allows 32 bit <=> 8 bit conversions without copies if SK_CPU_BENDIAN.
-
-class SkSHA1 : public SkWStream {
-public:
-    SkSHA1();
-
-    /** Processes input, adding it to the digest.
-     *  Note that this treats the buffer as a series of uint8_t values.
-     */
-    bool write(const void* buffer, size_t size) override {
-        update(reinterpret_cast<const uint8_t*>(buffer), size);
-        return true;
-    }
-
-    size_t bytesWritten() const override { return SkToSizeT(this->byteCount); }
-
-    /** Processes input, adding it to the digest. Calling this after finish is undefined. */
-    void update(const uint8_t* input, size_t length);
-
-    struct Digest {
-        uint8_t data[20];
-    };
-
-    /** Computes and returns the digest. */
-    void finish(Digest& digest);
-
-private:
-    // number of bytes, modulo 2^64
-    uint64_t byteCount;
-
-    // state (ABCDE)
-    uint32_t state[5];
-
-    // input buffer
-    uint8_t buffer[64];
-};
-
-#endif