Fix mma/mmma by making gettop canonicalize TOP when set

Bug: 17253957
Change-Id: Ifd6d5984f63981e1f99b6ae6f9459c2801588459
diff --git a/envsetup.sh b/envsetup.sh
index 2c74b2d..754ecfa 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -629,7 +629,8 @@
 {
     local TOPFILE=build/core/envsetup.mk
     if [ -n "$TOP" -a -f "$TOP/$TOPFILE" ] ; then
-        echo $TOP
+        # The following circumlocution ensures we remove symlinks from TOP.
+        (cd $TOP; PWD= /bin/pwd)
     else
         if [ -f $TOPFILE ] ; then
             # The following circumlocution (repeated below as well) ensures