[tools/perf] Fix unit name in jetstream2 benchmark

'number' is not a valid unit name, should use 'count' instead.

Bug: 1015192
Change-Id: Ide4363f7faf8411bd27e68e186df19e9e6ee0f13
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1865219Reviewed-by: Juan Antonio Navarro Pérez <perezju@chromium.org>
Commit-Queue: Mikhail Khokhlov <khokhlov@google.com>
Cr-Commit-Position: refs/heads/master@{#706863}

tools/perf/page_sets/jetstream2_pages.py

@@ -66,7 +66,7 @@ class Jetstream2Story(press_story.PressStory):
           benchmark, 'score', v['Score'],
           description='Geometric mean of the iterations')
       self.AddMeasurement(
-          '%s.Iterations' % benchmark, 'number', v['Iterations'],
+          '%s.Iterations' % benchmark, 'count', v['Iterations'],
           description='Total number of iterations')
       for sub_k, sub_v in v['SubResults'].iteritems():
         self.AddMeasurement('%s.%s' % (benchmark, sub_k), 'score', sub_v)