message: Fix signed int overflow issue in tensor_id.cc
  When a node name has a long numeric suffix, e.g.,
  "foo/y_0/gradient_debug_09684b60f2184c67b744721915034528" (as has happened with tfdbg GradientsDebugger),
  the parsing algorithm in ParseTensorName() may experience signed int overflow. Replacing the types with "unsigned int" resolves the issue.
diff: @@ -34,8 +34,8 @@ TensorId ParseTensorName(StringPiece name) {
  // whole name string forms the first part of the tensor name.
  const char* base = name.data();
  const char* p = base + name.size() - 1;
  - int index = 0;
  - int mul = 1;
  + unsigned int index = 0;
  + unsigned int mul = 1;
  while (p > base && (*p >= '0' && *p <= '9')) {
  index += ((*p - '0') * mul);
  mul *= 10;
  