[native bridge] Add test to verify code_cache existance.

Bug: 18027433
Change-Id: I760acfdc3d109344a0d4fb25ae5d3f067997c547
diff --git a/runtime/native_bridge_art_interface.cc b/runtime/native_bridge_art_interface.cc
index b0d8e87..f598e27 100644
--- a/runtime/native_bridge_art_interface.cc
+++ b/runtime/native_bridge_art_interface.cc
@@ -119,7 +119,6 @@
 #ifndef __APPLE__  // Mac OS does not support CLONE_NEWNS.
   if (unshare(CLONE_NEWNS) == -1) {
     LOG(WARNING) << "Could not create mount namespace.";
-    return;
   }
   android::PreInitializeNativeBridge(dir.c_str(), GetInstructionSetString(kRuntimeISA));
 #endif
diff --git a/test/115-native-bridge/expected.txt b/test/115-native-bridge/expected.txt
index a5eedc6..16a71e4 100644
--- a/test/115-native-bridge/expected.txt
+++ b/test/115-native-bridge/expected.txt
@@ -1,3 +1,4 @@
+Code cache exists: './code_cache'.
 Native bridge initialized.
 Checking for getEnvValues.
 Ready for native bridge tests.
diff --git a/test/115-native-bridge/nativebridge.cc b/test/115-native-bridge/nativebridge.cc
index 442f99c..23145e3 100644
--- a/test/115-native-bridge/nativebridge.cc
+++ b/test/115-native-bridge/nativebridge.cc
@@ -23,6 +23,7 @@
 #include "jni.h"
 #include "stdio.h"
 #include "unistd.h"
+#include "sys/stat.h"
 
 #include "nativebridge/native_bridge.h"
 
@@ -208,7 +209,13 @@
 
 // NativeBridgeCallbacks implementations
 extern "C" bool native_bridge_initialize(const android::NativeBridgeRuntimeCallbacks* art_cbs,
-                                         const char* private_dir, const char* isa) {
+                                         const char* app_code_cache_dir, const char* isa) {
+  struct stat st;
+  if ((app_code_cache_dir != nullptr)
+      && (stat(app_code_cache_dir, &st) == 0)
+      && S_ISDIR(st.st_mode)) {
+    printf("Code cache exists: '%s'.\n", app_code_cache_dir);
+  }
   if (art_cbs != nullptr) {
     gNativeBridgeArtCallbacks = art_cbs;
     printf("Native bridge initialized.\n");