Reduce kernel_IdlePerf test time from 40 minutes to 20 minutes

TEST=run kernel_IdlePerf
BUG=b:154426893

Change-Id: I94ad8887ed0ae0273fce3ef5a457daa08f816651
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/2280281
Reviewed-by: Ross Zwisler <zwisler@google.com>
Commit-Queue: Joel Fernandes <joelaf@google.com>
Tested-by: Joel Fernandes <joelaf@google.com>
diff --git a/server/site_tests/kernel_IdlePerf/kernel_IdlePerf.py b/server/site_tests/kernel_IdlePerf/kernel_IdlePerf.py
old mode 100644
new mode 100755
index 0c96a46..b555155
--- a/server/site_tests/kernel_IdlePerf/kernel_IdlePerf.py
+++ b/server/site_tests/kernel_IdlePerf/kernel_IdlePerf.py
@@ -56,7 +56,8 @@
 # regression.
 # The exact page set selected is a mix of real pages (e.g. blogspot_2018) and
 # synthetic (e.g. transform_transitions_js_block)
-PAGES = ['blogspot_2018', 'twitter_2018', 'wikipedia_2018', 'transform_transitions_js_block', 'throughput_scrolling_passive_handler']
+# For a longer test,'twitter_2018', 'wikipedia_2018' can be added to PAGES.
+PAGES = ['blogspot_2018', 'transform_transitions_js_block', 'throughput_scrolling_passive_handler']
 
 # Benchmark to run
 BENCHMARK = 'rendering.desktop'