Make atrace HAL optional am: 892624d06d am: 446597a2cc
am: 400c166293

Change-Id: I6dd5fd9f12df926f8feec867332e23af18c3f2d0
diff --git a/compatibility_matrices/compatibility_matrix.current.xml b/compatibility_matrices/compatibility_matrix.current.xml
index 89855a0..0540ef1 100644
--- a/compatibility_matrices/compatibility_matrix.current.xml
+++ b/compatibility_matrices/compatibility_matrix.current.xml
@@ -1,5 +1,5 @@
 <compatibility-matrix version="1.0" type="framework" level="4">
-    <hal format="hidl" optional="false">
+    <hal format="hidl" optional="true">
         <name>android.hardware.atrace</name>
         <version>1.0</version>
         <interface>