[libc++] Extend check for non-ASCII characters to src/, test/ and benchmarks/

Differential Revision: https://reviews.llvm.org/D132180

NOKEYCHECK=True
GitOrigin-RevId: 355e0ce3c5366bd0b564a25e4b6675353da3c53e
diff --git a/src/iostream.cpp b/src/iostream.cpp
index 6164fd7..a8948ac 100644
--- a/src/iostream.cpp
+++ b/src/iostream.cpp
@@ -109,8 +109,8 @@
 
 class DoIOSInit {
 public:
-	DoIOSInit();
-	~DoIOSInit();
+    DoIOSInit();
+    ~DoIOSInit();
 };
 
 DoIOSInit::DoIOSInit()