Fix incorrect proguard keepfile generation for fields.

Field's type for an array was being printed with extra "[]" at the end.
E.g. "int[][]" instead of "int[]".

Change-Id: I27a915b74a4d996b3ac04840b825e8c2ffd13e4e
diff --git a/src/com/google/doclava/Stubs.java b/src/com/google/doclava/Stubs.java
index 560acef..d396e88 100644
--- a/src/com/google/doclava/Stubs.java
+++ b/src/com/google/doclava/Stubs.java
@@ -1518,7 +1518,7 @@
     }
 
     keepListWriter.print(" ");
-    keepListWriter.print(getCleanTypeName(fi.type()) + fi.type().dimension());
+    keepListWriter.print(getCleanTypeName(fi.type()));
 
     keepListWriter.print(" ");
     keepListWriter.print(fi.name());