Revert "Make File.create() fail when a directory exists at the same path"

runtime/bin/file_macos.cc

Index: runtime/bin/file_macos.cc
diff --git a/runtime/bin/file_macos.cc b/runtime/bin/file_macos.cc
index d1259f757fc3d875b80339b98434b06dca10553b..2b32bc1899fc263d5a36b3b8ee75a76c652ecd7e 100644
--- a/runtime/bin/file_macos.cc
+++ b/runtime/bin/file_macos.cc
@@ -230,8 +230,7 @@ File* File::OpenStdio(int fd) {
 bool File::Exists(const char* name) {
   struct stat st;
   if (NO_RETRY_EXPECTED(stat(name, &st)) == 0) {
-    // Everything but a directory and a link is a file to Dart.
-    return !S_ISDIR(st.st_mode) && !S_ISLNK(st.st_mode);
+    return S_ISREG(st.st_mode);
   } else {
     return false;
   }
@@ -243,22 +242,7 @@ bool File::Create(const char* name) {
   if (fd < 0) {
     return false;
   }
-  // File.create returns a File, so we shouldn't be giving the illusion that the
-  // call has created a file or that a file already exists if there is already
-  // an entity at the same path that is a directory or a link.
-  bool is_file = true;
-  struct stat st;
-  if (NO_RETRY_EXPECTED(fstat(fd, &st)) == 0) {
-    if (S_ISDIR(st.st_mode)) {
-      errno = EISDIR;
-      is_file = false;
-    } else if (S_ISLNK(st.st_mode)) {
-      errno = ENOENT;
-      is_file = false;
-    }
-  }
-  FDUtils::SaveErrorAndClose(fd);
-  return is_file;
+  return (close(fd) == 0);
 }