Avoid |repo info| when cleaning projects

Change-Id: I48deebca82224b121d6f6e1c437c64387acd29af

vendorsetup.sh

@@ -73,8 +73,7 @@ __abandon_branch()
          return 1
       fi
     fi
-    local currentRev=$(${REPO} info -l . | sed -ne 's/^Current revision: \(\w*\)$/\1/p')
-    git reset --hard $currentRev
+    git reset --hard HEAD
     git clean -dfx
     ${REPO} abandon b2g_autogen_ephemeral_branch .
   fi
@@ -237,8 +236,7 @@ __patch_tree()
                      fi
                   fi
                   # Ensure the project is clean before applying patches to it
-                  local currentRev=$(${REPO} info -l . | sed -ne 's/^Current revision: \(\w*\)$/\1/p')
-                  git reset --hard $currentRev
+                  git reset --hard HEAD
                   git clean -dfx
 
                   declare -a PATCHNAME