predictors: Remove unused histograms for speculative_prefetch_predictor.

tools/metrics/common/presubmit_util.py

Index: tools/metrics/common/presubmit_util.py
diff --git a/tools/metrics/common/presubmit_util.py b/tools/metrics/common/presubmit_util.py
index 3010c2eda1e5b7f90da913bcd77520d1e4a1d9eb..73fde302a4633625252af81d189c50c2707ab0a7 100644
--- a/tools/metrics/common/presubmit_util.py
+++ b/tools/metrics/common/presubmit_util.py
@@ -7,8 +7,10 @@ import sys
 import logging
 import shutil
 
-sys.path.insert(1, os.path.join(sys.path[0], '..', '..', 'python'))
-import google.path_utils
+sys.path.append(
+    os.path.join(os.path.dirname(os.path.abspath(__file__)),
+                 os.pardir, os.pardir, 'python', 'google'))
+import path_utils
 
 import diff_util
 
@@ -34,7 +36,7 @@ def DoPresubmitMain(argv, original_filename, backup_filename, script_name,
   # Otherwise, use the one residing in the same directory as this script.
   xml_dir = os.getcwd()
   if not os.path.isfile(os.path.join(xml_dir, original_filename)):
-    xml_dir = google.path_utils.ScriptDir()
+    xml_dir = path_utils.ScriptDir()
 
   xml_path = os.path.join(xml_dir, original_filename)