clean-up libutils includes

moved Foo.h as first include of Foo.cpp, and
removed redundant includes.

Made NativeHandle non virtual.


Test: run & compile
Bug: n/a

Change-Id: I37fa746cd42c9ba23aba181f84cb6c619386406a
diff --git a/libutils/CallStack.cpp b/libutils/CallStack.cpp
index 699da74..bd6015e 100644
--- a/libutils/CallStack.cpp
+++ b/libutils/CallStack.cpp
@@ -16,9 +16,10 @@
 
 #define LOG_TAG "CallStack"
 
+#include <utils/CallStack.h>
+
 #include <memory>
 
-#include <utils/CallStack.h>
 #include <utils/Printer.h>
 #include <utils/Errors.h>
 #include <utils/Log.h>