Replace base::str[n]casecmp with helper functions.

sql/connection.cc

Index: sql/connection.cc
diff --git a/sql/connection.cc b/sql/connection.cc
index d1b104908c988089729ae0050f9aff7da7016f7f..d07d425eb1721ac5b1da4c78198caac030fd4744 100644
--- a/sql/connection.cc
+++ b/sql/connection.cc
@@ -992,7 +992,8 @@ bool Connection::DoesColumnExist(const char* table_name,
     return false;
 
   while (statement.Step()) {
-    if (!base::strcasecmp(statement.ColumnString(1).c_str(), column_name))
+    if (base::EqualsCaseInsensitiveASCII(statement.ColumnString(1),
+                                         column_name))
       return true;
   }
   return false;