adb: move AdbCloser to its rightful place.

Test: mma
Change-Id: Ie74c49e8abf72f594a35d04b2b0d99b96f58f8d0
diff --git a/adb/adb_unique_fd.cpp b/adb/adb_unique_fd.cpp
index 2079be1..58e768e 100644
--- a/adb/adb_unique_fd.cpp
+++ b/adb/adb_unique_fd.cpp
@@ -21,6 +21,10 @@
 
 #include "sysdeps.h"
 
+void AdbCloser::Close(int fd) {
+    adb_close(fd);
+}
+
 #if !defined(_WIN32)
 bool Pipe(unique_fd* read, unique_fd* write, int flags) {
     int pipefd[2];
diff --git a/adb/adb_utils.cpp b/adb/adb_utils.cpp
index 0c3327f..ffac315 100644
--- a/adb/adb_utils.cpp
+++ b/adb/adb_utils.cpp
@@ -274,10 +274,6 @@
     return android_dir;
 }
 
-void AdbCloser::Close(int fd) {
-    adb_close(fd);
-}
-
 int syntax_error(const char* fmt, ...) {
     fprintf(stderr, "adb: usage: ");