Made sizeof code simpler and more obviously correct.

base/strings/safe_sprintf_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/strings/safe_sprintf.h"
 
 #include <stdio.h>
 #include <string.h>
 
 #include <limits>
@@ skipping 43 matching lines @@
   EXPECT_EQ('X', buf[1]);
   buf[0] = 'X';
 }
 
 TEST(SafeSPrintfTest, NoArguments) {
   // Output a text message that doesn't require any substitutions. This
   // is roughly equivalent to calling strncpy() (but unlike strncpy(), it does
   // always add a trailing NUL; it always deduplicates '%' characters).
   static const char text[] = "hello world";
   char ref[20], buf[20];
-  memset(ref, 'X', sizeof(char) * arraysize(buf));
+  memset(ref, 'X', sizeof(ref));
   memcpy(buf, ref, sizeof(buf));
 
   // A negative buffer size should always result in an error.
   EXPECT_EQ(-1, SafeSNPrintf(buf, static_cast<size_t>(-1), text));
   EXPECT_TRUE(!memcmp(buf, ref, sizeof(buf)));
 
   // Zero buffer size should always result in an error.
   EXPECT_EQ(-1, SafeSNPrintf(buf, 0, text));
   EXPECT_TRUE(!memcmp(buf, ref, sizeof(buf)));
 
@@ skipping 675 matching lines @@
   void *ptr = str;
   char buf[40];
   EXPECT_EQ(10, SafeSPrintf(buf, "%p", str));
   EXPECT_EQ("0x80000000", std::string(buf));
   EXPECT_EQ(10, SafeSPrintf(buf, "%p", ptr));
   EXPECT_EQ("0x80000000", std::string(buf));
 }
 
 }  // namespace strings
 }  // namespace base