Move the compiler into C++.

Change-Id: Idffbdb02c29e2be03a75f5a0a664603f2299504a
diff --git a/vm/compiler/codegen/arm/CalloutHelper.h b/vm/compiler/codegen/arm/CalloutHelper.h
index 931cf0f..3bfb299 100644
--- a/vm/compiler/codegen/arm/CalloutHelper.h
+++ b/vm/compiler/codegen/arm/CalloutHelper.h
@@ -19,6 +19,10 @@
 #ifndef _DALVIK_VM_COMPILER_CODEGEN_ARM_CALLOUT_HELPER_H
 #define _DALVIK_VM_COMPILER_CODEGEN_ARM_CALLOUT_HELPER_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /*
  * Declare/comment prototypes of all native callout functions invoked by the
  * JIT'ed code here and use the LOAD_FUNC_ADDR macro to load the address into
@@ -121,4 +125,8 @@
  *      dvmLockObject           // MONITOR_ENTER
  */
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* _DALVIK_VM_COMPILER_CODEGEN_ARM_CALLOUT_HELPER_H */