Prepare for moving grit to its own open-source project. This mostly

tools/grit/grit/testdata/tools/grit/resource_ids

Index: tools/grit/grit/testdata/tools/grit/resource_ids
diff --git a/tools/grit/resource_ids b/tools/grit/grit/testdata/tools/grit/resource_ids
similarity index 97%
copy from tools/grit/resource_ids
copy to tools/grit/grit/testdata/tools/grit/resource_ids
index b8d09ec708a4496273b36f9557efe6769fa9a774..d8f71ff42f479b5544bc32a0898e081411a4f170 100644
--- a/tools/grit/resource_ids
+++ b/tools/grit/grit/testdata/tools/grit/resource_ids
@@ -7,10 +7,15 @@
 # across all the grd files.  If you are adding a new grd file, please add
 # a new entry to this file.
 #
+# The first entry in the file, SRCDIR, is special: It is a relative path from
+# this file to the base of your checkout.
+#
 # http://msdn.microsoft.com/en-us/library/t2zechd4(VS.71).aspx says that the
 # range for IDR_ is 1 to 28,671 and the range for IDS_ is 1 to 32,767 and
 # common convention starts practical use of IDs at 100 or 101.
 {
+  "SRCDIR": "../..",
+
   "chrome/browser/browser_resources.grd": {
     "includes": [500],
   },