Revert "Replaced android::Vector with std::vector."

b/19148482

This reverts commit 93d6bc872b7d9fba63abfa7513d56b38d9c3d371.

I also made some changes to Make it work with HEAD.

Change-Id: I5e516976ec1d85ffe1cf388c01795348a9441982
diff --git a/rsElement.h b/rsElement.h
index ccf69eb..9374c64 100644
--- a/rsElement.h
+++ b/rsElement.h
@@ -17,8 +17,6 @@
 #ifndef ANDROID_STRUCTURED_ELEMENT_H
 #define ANDROID_STRUCTURED_ELEMENT_H
 
-#include <vector>
-
 #include "rsComponent.h"
 #include "rsUtils.h"
 #include "rsInternalDefines.h"
@@ -172,7 +170,7 @@
     ~ElementState();
 
     // Cache of all existing elements.
-    std::vector<Element *> mElements;
+    Vector<Element *> mElements;
 };