testrunner.py: log error message if failed to import sqlite3 package

--HG--
extra : transplant_source : p%03%AA%98Y%87%06%F1%F2O%7B%B3qnL%066%1F%A9%21

greentest/testrunner.py

@@ -51,10 +51,12 @@ import platform
 
 try:
     import sqlite3
-except ImportError:
+except ImportError, ex:
+    sys.stderr.write('Failed to import sqlite3: %s\n' % ex)
     try:
         import pysqlite2.dbapi2 as sqlite3
-    except ImportError:
+    except ImportError, ex:
+        sys.stderr.write('Failed to import pysqlite2.dbapi2: %s\n' % ex)
         sqlite3 = None
 
 _column_types = {'time': 'real'}