remove unused locals

found by findbugs
http://b/issue?id=1856758
diff --git a/src/com/android/browser/BrowserActivity.java b/src/com/android/browser/BrowserActivity.java
index 155942e..e15064b 100644
--- a/src/com/android/browser/BrowserActivity.java
+++ b/src/com/android/browser/BrowserActivity.java
@@ -294,8 +294,6 @@
         boolean mDoOverwrite = false;
         String pluginsPath;
         Context mContext;
-        File pluginsDir;
-        AssetManager manager;
 
         public CopyPlugins (boolean overwrite, Context context) {
             mDoOverwrite = overwrite;