Fix lock contention in Attention

Call checkAttention() sits in the critical path inside the PowerManager.
To avoid the lock contention, don't call into the PackageManager.
Specifically, checking the configuration with the PackageManager is
redundant since it's already done by SystemServer - it won't start the
AttentionManagerService if it's not configured.

Bug: 169427927
Test: manually
Change-Id: I46ca7a6ce01d2229521f1fe12a80440024465c67

services/core/java/com/android/server/attention/AttentionManagerService.java

@@ -172,7 +172,7 @@ public class AttentionManagerService extends SystemService {
      */
     @VisibleForTesting
     protected boolean isAttentionServiceSupported() {
-        return isServiceEnabled() && isServiceConfigured(mContext);
+        return isServiceEnabled();
     }
 
     private boolean isServiceEnabled() {