predictors: Track whether resources have validators, and require validation.

tools/resource_prefetch_predictor/prefetch_predictor_tool.py

Index: tools/resource_prefetch_predictor/prefetch_predictor_tool.py
diff --git a/tools/resource_prefetch_predictor/prefetch_predictor_tool.py b/tools/resource_prefetch_predictor/prefetch_predictor_tool.py
index bbb6162bef3c87fa6a214bf898bc71878f35c8f3..fad71305bbbe46a8bccdd3ffa286023bb0eb9ebb 100755
--- a/tools/resource_prefetch_predictor/prefetch_predictor_tool.py
+++ b/tools/resource_prefetch_predictor/prefetch_predictor_tool.py
@@ -27,11 +27,13 @@ class Entry(object):
   """Represents an entry in the predictor database."""
   HEADER = (
       'score,main_page_url,resource_type,number_of_hits,number_of_misses,'
-      'consecutive_misses,average_position,confidence,resource_url')
+      'consecutive_misses,average_position,confidence,has_validators,'
+      'always_revalidate,resource_url')
 
   def __init__(
       self, main_page_url, resource_url, resource_type, number_of_hits,
-      number_of_misses, consecutive_misses, average_position, priority):
+      number_of_misses, consecutive_misses, average_position, priority,
+      has_validators, always_revalidate):
     self.main_page_url = main_page_url
     self.resource_url = resource_url
     self.resource_type = resource_type
@@ -40,6 +42,8 @@ class Entry(object):
     self.consecutive_misses = int(consecutive_misses)
     self.average_position = int(average_position)
     self.priority = int(priority)
+    self.has_validators = bool(int(has_validators))
+    self.always_revalidate = bool(int(always_revalidate))
     self.confidence = float(number_of_hits) / (
         number_of_hits + number_of_misses)
     self.score = self._Score()
@@ -58,11 +62,11 @@ class Entry(object):
     return Entry(*row)
 
   def __str__(self):
-    return '%f,%s,%d,%d,%d,%d,%d,%f,%d\t%s' % (
+    return '%f,%s,%d,%d,%d,%d,%d,%f,%d,%d,%d\t%s' % (
         self.score, self.main_page_url, self.resource_type,
         self.number_of_hits, self.number_of_misses, self.consecutive_misses,
         self.average_position, self.confidence, self.priority,
-        self.resource_url)
+        self.has_validators, self.always_revalidate, self.resource_url)
 
 
 def FilterAndSort(entries, domain):
@@ -81,7 +85,8 @@ def DatabaseStats(filename, domain):
   connection = sqlite3.connect(filename)
   c = connection.cursor()
   query = ('SELECT main_page_url, resource_url, resource_type, number_of_hits, '
-           'number_of_misses, consecutive_misses, average_position, priority '
+           'number_of_misses, consecutive_misses, average_position, priority, '
+           'has_validators, always_revalidate '
            'FROM resource_prefetch_predictor_host')
   entries = [Entry.FromRow(row) for row in c.execute(query)]
   prefetched = FilterAndSort(entries, domain)