SF: Renaming IdleTimer to OneShotTimer

IdleTimer class is used for more than just idle timer, so renaming the
class to a more appropriate name.

Test: manual
Bug: 132811842

Change-Id: Iabfaa28038dc90430a51536ef874618e35ed9014
diff --git a/services/surfaceflinger/tests/unittests/Android.bp b/services/surfaceflinger/tests/unittests/Android.bp
index f842d61..4917bc2 100644
--- a/services/surfaceflinger/tests/unittests/Android.bp
+++ b/services/surfaceflinger/tests/unittests/Android.bp
@@ -42,7 +42,7 @@
         "DisplayTransactionTest.cpp",
         "EventControlThreadTest.cpp",
         "EventThreadTest.cpp",
-        "IdleTimerTest.cpp",
+        "OneShotTimerTest.cpp",
         "LayerHistoryTest.cpp",
         "LayerMetadataTest.cpp",
         "SchedulerTest.cpp",