stagefright: move asString to android namespace

Change-Id: If95a60538d26ac04cf2c7a92026449503bc971c5
diff --git a/include/media/stagefright/foundation/ADebug.h b/include/media/stagefright/foundation/ADebug.h
index 65f415a..564b3f7 100644
--- a/include/media/stagefright/foundation/ADebug.h
+++ b/include/media/stagefright/foundation/ADebug.h
@@ -24,8 +24,9 @@
 #include <media/stagefright/foundation/AString.h>
 #include <utils/Log.h>
 
-inline static const char *asString(android::status_t i, const char *def = "??") {
-    using namespace android;
+namespace android {
+
+inline static const char *asString(status_t i, const char *def = "??") {
     switch (i) {
         case NO_ERROR:              return "NO_ERROR";
         case UNKNOWN_ERROR:         return "UNKNOWN_ERROR";
@@ -49,8 +50,6 @@
     }
 }
 
-namespace android {
-
 #define LITERAL_TO_STRING_INTERNAL(x)    #x
 #define LITERAL_TO_STRING(x) LITERAL_TO_STRING_INTERNAL(x)