Revert "Add a way to turn off unique_fd's operator int."

This reverts commit 93d63c010ae24ff58acb70216bfcb93e3c73019a.

Reason for revert: b/131312539 - All aosp-master-with-phones phones failing boot / health check.

Change-Id: Id4239f93484b7d6b8d9bcd355a59cbd40d9766e2
diff --git a/adb/adb_utils.cpp b/adb/adb_utils.cpp
index cf5fbc8..9791769 100644
--- a/adb/adb_utils.cpp
+++ b/adb/adb_utils.cpp
@@ -234,15 +234,15 @@
 
 #if !defined(_WIN32)
 // Windows version provided in sysdeps_win32.cpp
-bool set_file_block_mode(borrowed_fd fd, bool block) {
-    int flags = fcntl(fd.get(), F_GETFL, 0);
+bool set_file_block_mode(int fd, bool block) {
+    int flags = fcntl(fd, F_GETFL, 0);
     if (flags == -1) {
-        PLOG(ERROR) << "failed to fcntl(F_GETFL) for fd " << fd.get();
+        PLOG(ERROR) << "failed to fcntl(F_GETFL) for fd " << fd;
         return false;
     }
     flags = block ? (flags & ~O_NONBLOCK) : (flags | O_NONBLOCK);
-    if (fcntl(fd.get(), F_SETFL, flags) != 0) {
-        PLOG(ERROR) << "failed to fcntl(F_SETFL) for fd " << fd.get() << ", flags " << flags;
+    if (fcntl(fd, F_SETFL, flags) != 0) {
+        PLOG(ERROR) << "failed to fcntl(F_SETFL) for fd " << fd << ", flags " << flags;
         return false;
     }
     return true;