Re-land r9059 with empty cityhash.gyp, instead of deleted cityhash.gyp

src/utils/SkBitmapHasher.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkBitmapHasher.h"
 #include "SkEndian.h"
 #include "SkImageEncoder.h"
 
-#ifdef BITMAPHASHER_USES_TRUNCATED_MD5
 #include "SkMD5.h"
-#else
-#include "SkCityHash.h"
-#include "SkStream.h"
-#endif
 
 /**
  * Write an int32 value to a stream in little-endian order.
  */
 static void write_int32_to_buffer(uint32_t val, SkWStream* out) {
     val = SkEndian_SwapLE32(val);
     for (size_t byte = 0; byte < 4; ++byte) {
         out->write8((uint8_t)(val & 0xff));
         val = val >> 8;
     }
 }
 
 /**
  * Return the first 8 bytes of a bytearray, encoded as a little-endian uint64.
  */
 static inline uint64_t first_8_bytes_as_uint64(const uint8_t *bytearray) {
     return SkEndian_SwapLE64(*(reinterpret_cast<const uint64_t *>(bytearray)));
 }
 
 /*static*/ bool SkBitmapHasher::ComputeDigestInternal(const SkBitmap& bitmap,
                                                       SkHashDigest *result) {
-#ifdef BITMAPHASHER_USES_TRUNCATED_MD5
     SkMD5 out;
-#else
-    size_t pixelBufferSize = bitmap.width() * bitmap.height() * 4;
-    size_t totalBufferSize = pixelBufferSize + 2 * sizeof(uint32_t);
-
-    SkAutoMalloc bufferManager(totalBufferSize);
-    char *bufferStart = static_cast<char *>(bufferManager.get());
-    SkMemoryWStream out(bufferStart, totalBufferSize);
-#endif
 
     // start with the x/y dimensions
     write_int32_to_buffer(SkToU32(bitmap.width()), &out);
     write_int32_to_buffer(SkToU32(bitmap.height()), &out);
 
     // add all the pixel data
     SkAutoTDelete<SkImageEncoder> enc(CreateARGBImageEncoder());
     if (!enc->encodeStream(&out, bitmap, SkImageEncoder::kDefaultQuality)) {
         return false;
     }
 
-#ifdef BITMAPHASHER_USES_TRUNCATED_MD5
     SkMD5::Digest digest;
     out.finish(digest);
     *result = first_8_bytes_as_uint64(digest.data);
-#else
-    *result = SkCityHash::Compute64(bufferStart, totalBufferSize);
-#endif
     return true;
 }
 
 /*static*/ bool SkBitmapHasher::ComputeDigest(const SkBitmap& bitmap, SkHashDigest *result) {
     if (ComputeDigestInternal(bitmap, result)) {
         return true;
     }
 
     // Hmm, that didn't work. Maybe if we create a new
     // kARGB_8888_Config version of the bitmap it will work better?
     SkBitmap copyBitmap;
     if (!bitmap.copyTo(&copyBitmap, SkBitmap::kARGB_8888_Config)) {
         return false;
     }
     return ComputeDigestInternal(copyBitmap, result);
 }