Switch to narrowest scope for a static, per suggestion in a review on another file.

components/webdata/autofill/autofill_table.cc

Index: components/webdata/autofill/autofill_table.cc
diff --git a/components/webdata/autofill/autofill_table.cc b/components/webdata/autofill/autofill_table.cc
index 318458db258bedc873d4878cdb6fd8cdd8436989..34dc348f4fe2e1a4636213b3bb62bd46d40a99e1 100644
--- a/components/webdata/autofill/autofill_table.cc
+++ b/components/webdata/autofill/autofill_table.cc
@@ -322,9 +322,10 @@ bool RemoveAutofillProfilePieces(const std::string& guid, sql::Connection* db) {
   return s3.Run();
 }
 
-int table_key = 0;
-
 WebDatabaseTable::TypeKey GetKey() {
+  // We just need a unique constant. Use the address of a static that
+  // COMDAT folding won't touch in an optimizing linker.
+  static int table_key = 0;
   return reinterpret_cast<void*>(&table_key);
 }