Remove v8stdint.h, it doesn't serve a purpose anymore.

test/unittests/base/division-by-constant-unittest.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Check all examples from table 10-1 of "Hacker's Delight".
 
 #include "src/base/division-by-constant.h"
 
+#include <stdint.h>
+
 #include <ostream>  // NOLINT
 
 #include "testing/gtest-support.h"
 
 namespace v8 {
 namespace base {
 
 template <class T>
 std::ostream& operator<<(std::ostream& os,
                          const MagicNumbersForDivision<T>& mag) {
@@ skipping 104 matching lines @@
   EXPECT_EQ(M64(0xCCCCCCCCCCCCCCCDULL, 3, false), u64(10));
   EXPECT_EQ(M64(0x2E8BA2E8BA2E8BA3ULL, 1, false), u64(11));
   EXPECT_EQ(M64(0xAAAAAAAAAAAAAAABULL, 3, false), u64(12));
   EXPECT_EQ(M64(0x47AE147AE147AE15ULL, 5, true), u64(25));
   EXPECT_EQ(M64(0x0624DD2F1A9FBE77ULL, 7, true), u64(125));
   EXPECT_EQ(M64(0x346DC5D63886594BULL, 7, false), u64(625));
 }
 
 }  // namespace base
 }  // namespace v8