Add UMA histograms for GPU driver bug workaround entries.

tools/metrics/histograms/update_gpu_driver_bug_workaround_entries.py

Index: tools/metrics/histograms/update_gpu_driver_bug_workaround_entries.py
diff --git a/tools/metrics/histograms/update_gpu_driver_bug_workaround_entries.py b/tools/metrics/histograms/update_gpu_driver_bug_workaround_entries.py
new file mode 100755
index 0000000000000000000000000000000000000000..1250dd7471c125da91dd800efcb2dff1d5eca91e
--- /dev/null
+++ b/tools/metrics/histograms/update_gpu_driver_bug_workaround_entries.py
@@ -0,0 +1,54 @@
+#!/usr/bin/env python
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Updates GpuDriverBugWorkaroundEntry enum in histograms.xml file with values
+ read from gpu_driver_bug_list.json.
+
+If the file was pretty-printed, the updated version is pretty-printed too.
+"""
+
+import os.path
+import re
+import sys
+
+sys.path.append(os.path.join(os.path.dirname(__file__), '..', 'common'))
+import path_util
+import json
+
+import update_histogram_enum
+
+
+GPU_DRIVER_BUG_WORKAROUND_PATH = 'gpu/config/gpu_driver_bug_list.json'
+
+
+def ReadGpuDriverBugEntries(filename):
+  """Reads in the gpu driver bug list, returning a dictionary mapping
+  workaround ids to descriptions.
+  """
+  # Read the file as a list of lines
+  with open(path_util.GetInputFile(filename)) as f:
+    json_data = json.load(f)
+
+  entries = {}
+  entries[0] = '0: Recorded once every time this histogram is updated.'
+  for entry in json_data["entries"]:
+    entries[entry["id"]] = "%d: %s" % (entry["id"], entry["description"])
+  return entries
+
+
+def main():
+  if len(sys.argv) > 1:
+    print >>sys.stderr, 'No arguments expected!'
+    sys.stderr.write(__doc__)
+    sys.exit(1)
+
+  update_histogram_enum.UpdateHistogramFromDict(
+      'GpuDriverBugWorkaroundEntry',
+      ReadGpuDriverBugEntries(GPU_DRIVER_BUG_WORKAROUND_PATH),
+      GPU_DRIVER_BUG_WORKAROUND_PATH)
+
+
+if __name__ == '__main__':
+  main()